Remove an unused header file.

This was our only remaining BSD 4-clause file.

Test: N/A
Change-Id: I3a4042a92f1ff6ab7d3e1a0cd043952f98f0861e
diff --git a/libm/NOTICE b/libm/NOTICE
index 2deaac5..424725e 100644
--- a/libm/NOTICE
+++ b/libm/NOTICE
@@ -1303,38 +1303,3 @@
 
 -------------------------------------------------------------------
 
-SPDX-License-Identifier: BSD-4-Clause
-
-Copyright (c) 1988, 1993
-   The Regents of the University of California.  All rights reserved.
-
-Redistribution and use in source and binary forms, with or without
-modification, are permitted provided that the following conditions
-are met:
-1. Redistributions of source code must retain the above copyright
-   notice, this list of conditions and the following disclaimer.
-2. Redistributions in binary form must reproduce the above copyright
-   notice, this list of conditions and the following disclaimer in the
-   documentation and/or other materials provided with the distribution.
-3. All advertising materials mentioning features or use of this software
-   must display the following acknowledgement:
-   This product includes software developed by the University of
-   California, Berkeley and its contributors.
-4. Neither the name of the University nor the names of its contributors
-   may be used to endorse or promote products derived from this software
-   without specific prior written permission.
-
-THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
-ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
-IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
-ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
-FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
-DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
-OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
-HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
-LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
-OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
-SUCH DAMAGE.
-
--------------------------------------------------------------------
-
diff --git a/libm/upstream-freebsd/lib/msun/bsdsrc/mathimpl.h b/libm/upstream-freebsd/lib/msun/bsdsrc/mathimpl.h
deleted file mode 100644
index abf2996..0000000
--- a/libm/upstream-freebsd/lib/msun/bsdsrc/mathimpl.h
+++ /dev/null
@@ -1,76 +0,0 @@
-/*-
- * SPDX-License-Identifier: BSD-4-Clause
- *
- * Copyright (c) 1988, 1993
- *	The Regents of the University of California.  All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- * 3. All advertising materials mentioning features or use of this software
- *    must display the following acknowledgement:
- *	This product includes software developed by the University of
- *	California, Berkeley and its contributors.
- * 4. Neither the name of the University nor the names of its contributors
- *    may be used to endorse or promote products derived from this software
- *    without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- *
- *	@(#)mathimpl.h	8.1 (Berkeley) 6/4/93
- * $FreeBSD$
- */
-
-#ifndef _MATHIMPL_H_
-#define	_MATHIMPL_H_
-
-#include <sys/cdefs.h>
-#include <math.h>
-
-#include "../src/math_private.h"
-
-/*
- * TRUNC() is a macro that sets the trailing 27 bits in the mantissa of an
- * IEEE double variable to zero.  It must be expression-like for syntactic
- * reasons, and we implement this expression using an inline function
- * instead of a pure macro to avoid depending on the gcc feature of
- * statement-expressions.
- */
-#define	TRUNC(d)	(_b_trunc(&(d)))
-
-static __inline void
-_b_trunc(volatile double *_dp)
-{
-	uint32_t _lw;
-
-	GET_LOW_WORD(_lw, *_dp);
-	SET_LOW_WORD(*_dp, _lw & 0xf8000000);
-}
-
-struct Double {
-	double	a;
-	double	b;
-};
-
-/*
- * Functions internal to the math package, yet not static.
- */
-double	__exp__D(double, double);
-struct Double __log__D(double);
-
-#endif /* !_MATHIMPL_H_ */