Revert "Update to FreeBSD libm r336523."

This reverts commit f86ee10278116d211cfb08679416444e0e714cb5.

Incorrect result for fmodf(3.0f, 0f) = 1.0f breaks ART tests.

Bug: 111710419
Test: art/test/testrunner/testrunner.py -b -t 436-rem-float --target
Change-Id: I7eae68fb92740db33415d16418447bcbbd98ecba
diff --git a/libm/upstream-freebsd/lib/msun/src/e_fmod.c b/libm/upstream-freebsd/lib/msun/src/e_fmod.c
index 36f98d1..bad066a 100644
--- a/libm/upstream-freebsd/lib/msun/src/e_fmod.c
+++ b/libm/upstream-freebsd/lib/msun/src/e_fmod.c
@@ -12,7 +12,7 @@
  */
 
 #include <sys/cdefs.h>
-__FBSDID("$FreeBSD: head/lib/msun/src/e_fmod.c 336362 2018-07-17 07:42:14Z bde $");
+__FBSDID("$FreeBSD: head/lib/msun/src/e_fmod.c 305380 2016-09-04 12:01:32Z bde $");
 
 /* 
  * __ieee754_fmod(x,y)
@@ -42,7 +42,7 @@
     /* purge off exception values */
 	if((hy|ly)==0||(hx>=0x7ff00000)||	/* y=0,or x not finite */
 	  ((hy|((ly|-ly)>>31))>0x7ff00000))	/* or y is NaN */
-	    return nan_mix(x, y)/nan_mix(x, y);
+	    return (x*y)/(x*y);
 	if(hx<=hy) {
 	    if((hx<hy)||(lx<ly)) return x;	/* |x|<|y| return x */
 	    if(lx==ly)