Update to FreeBSD libm r336523.

This includes an ld128 powl, plus the clog* and cpow* families.

Also teach the NOTICE generator to strip SPDX-License-Identifier lines.

Bug: N/A
Test: ran tests
Change-Id: Ic8289d1253666a19468a4088884cf7540f1ec66d
diff --git a/libm/upstream-freebsd/lib/msun/src/s_csinhf.c b/libm/upstream-freebsd/lib/msun/src/s_csinhf.c
index 7f58b55..6e29f19 100644
--- a/libm/upstream-freebsd/lib/msun/src/s_csinhf.c
+++ b/libm/upstream-freebsd/lib/msun/src/s_csinhf.c
@@ -31,7 +31,7 @@
  */
 
 #include <sys/cdefs.h>
-__FBSDID("$FreeBSD: head/lib/msun/src/s_csinhf.c 326219 2017-11-26 02:00:33Z pfg $");
+__FBSDID("$FreeBSD: head/lib/msun/src/s_csinhf.c 336362 2018-07-17 07:42:14Z bde $");
 
 #include <complex.h>
 #include <math.h>
@@ -92,7 +92,8 @@
 		return (CMPLXF(x * cosf(y), INFINITY * sinf(y)));
 	}
 
-	return (CMPLXF((x + x) * (y - y), (x * x) * (y - y)));
+	return (CMPLXF(((long double)x + x) * (y - y),
+	    ((long double)x * x) * (y - y)));
 }
 
 float complex