Sync upstream FreeBSD libm.

Test: treehugger
Change-Id: I583a3e93821d512c975db34fc1610ffd22445d58
diff --git a/libm/upstream-freebsd/lib/msun/src/e_cosh.c b/libm/upstream-freebsd/lib/msun/src/e_cosh.c
index 246b5fb..071663e 100644
--- a/libm/upstream-freebsd/lib/msun/src/e_cosh.c
+++ b/libm/upstream-freebsd/lib/msun/src/e_cosh.c
@@ -14,7 +14,7 @@
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 
-/* __ieee754_cosh(x)
+/* cosh(x)
  * Method : 
  * mathematically cosh(x) if defined to be (exp(x)+exp(-x))/2
  *	1. Replace x by |x| (cosh(x) = cosh(-x)). 
@@ -43,7 +43,7 @@
 static const double one = 1.0, half=0.5, huge = 1.0e300;
 
 double
-__ieee754_cosh(double x)
+cosh(double x)
 {
 	double t,w;
 	int32_t ix;
@@ -65,12 +65,12 @@
 
     /* |x| in [0.5*ln2,22], return (exp(|x|)+1/exp(|x|)/2; */
 	if (ix < 0x40360000) {
-		t = __ieee754_exp(fabs(x));
+		t = exp(fabs(x));
 		return half*t+half/t;
 	}
 
     /* |x| in [22, log(maxdouble)] return half*exp(|x|) */
-	if (ix < 0x40862E42)  return half*__ieee754_exp(fabs(x));
+	if (ix < 0x40862E42)  return half*exp(fabs(x));
 
     /* |x| in [log(maxdouble), overflowthresold] */
 	if (ix<=0x408633CE)