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/e_remainderf.c b/libm/upstream-freebsd/lib/msun/src/e_remainderf.c
index b0014ae..89cd932 100644
--- a/libm/upstream-freebsd/lib/msun/src/e_remainderf.c
+++ b/libm/upstream-freebsd/lib/msun/src/e_remainderf.c
@@ -14,7 +14,7 @@
  */
 
 #include <sys/cdefs.h>
-__FBSDID("$FreeBSD$");
+__FBSDID("$FreeBSD: head/lib/msun/src/e_remainderf.c 336362 2018-07-17 07:42:14Z bde $");
 
 #include "math.h"
 #include "math_private.h"
@@ -36,10 +36,10 @@
 	hx &= 0x7fffffff;
 
     /* purge off exception values */
-	if(hp==0) return (x*p)/(x*p);	 	/* p = 0 */
-	if((hx>=0x7f800000)||			/* x not finite */
+	if((hp==0)||			 	/* p = 0 */
+	  (hx>=0x7f800000)||			/* x not finite */
 	  ((hp>0x7f800000)))			/* p is NaN */
-	    return ((long double)x*p)/((long double)x*p);
+	    return nan_mix(x, p)/nan_mix(x, p);
 
 
 	if (hp<=0x7effffff) x = __ieee754_fmodf(x,p+p);	/* now x < 2p */