For libm, use a macro for aliasing symbols.

Change-Id: Ibd42ebc387c2bf3eba9aa96091770915b4b34184
diff --git a/libm/x86/ceil.S b/libm/x86/ceil.S
index b992057..6302037 100644
--- a/libm/x86/ceil.S
+++ b/libm/x86/ceil.S
@@ -40,5 +40,4 @@
 	ret
 END(ceil)
 
-.globl ceill;
-.equ ceill, ceil;
+ALIAS_SYMBOL(ceill, ceil);