Update libm/NOTICE.

Change-Id: I6450766071d566fd24d9bbef9a8e9fdc5d26f3a7
diff --git a/libm/NOTICE b/libm/NOTICE
index 3c0e783..a88c351 100644
--- a/libm/NOTICE
+++ b/libm/NOTICE
@@ -622,17 +622,6 @@
 
 -------------------------------------------------------------------
 
-From: @(#)s_ilogb.c 5.1 93/09/24
-====================================================
-Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
-
-Developed at SunPro, a Sun Microsystems, Inc. business.
-Permission to use, copy, modify, and distribute this
-software is freely granted, provided that this notice
-is preserved.
-
--------------------------------------------------------------------
-
 SPDX-License-Identifier: BSD-2-Clause
 
 Copyright (c) 2003, Steven G. Kargl