Sync upstream FreeBSD libm.

Test: treehugger
Change-Id: I583a3e93821d512c975db34fc1610ffd22445d58
diff --git a/libm/upstream-freebsd/lib/msun/src/e_acosf.c b/libm/upstream-freebsd/lib/msun/src/e_acosf.c
index c9f62cc..64f1c5a 100644
--- a/libm/upstream-freebsd/lib/msun/src/e_acosf.c
+++ b/libm/upstream-freebsd/lib/msun/src/e_acosf.c
@@ -32,7 +32,7 @@
 qS1 = -7.0662963390e-01;
 
 float
-__ieee754_acosf(float x)
+acosf(float x)
 {
 	float z,p,q,r,w,s,c,df;
 	int32_t hx,ix;