For libm, use a macro for aliasing symbols.

Change-Id: Ibd42ebc387c2bf3eba9aa96091770915b4b34184
diff --git a/libm/x86/floor.S b/libm/x86/floor.S
index 2b815f3..b859736 100644
--- a/libm/x86/floor.S
+++ b/libm/x86/floor.S
@@ -40,5 +40,4 @@
 	ret
 END(floor)
 
-.globl floorl;
-.equ floorl, floor;
+ALIAS_SYMBOL(floorl, floor);