libm: remove aliasing issue.

See http://code.google.com/p/android/issues/detail?id=6697
for details about this change.

Change-Id: I516f00c6f3bc99b22be51669e4573246bdd6e33d
diff --git a/libm/src/s_frexpf.c b/libm/src/s_frexpf.c
index 89d464b..c18cd54 100644
--- a/libm/src/s_frexpf.c
+++ b/libm/src/s_frexpf.c
@@ -39,6 +39,6 @@
 	}
 	*eptr += (ix>>23)-126;
 	hx = (hx&0x807fffff)|0x3f000000;
-	*(int*)&x = hx;
+	SET_FLOAT_WORD(x,hx);
 	return x;
 }