Fix build by avoiding the _C_LABEL macro.

Change-Id: Ide367c2b65071388bd95fbc81a4ed6ae94aec4e4
diff --git a/libc/arch-x86_64/syscalls/fstat64.S b/libc/arch-x86_64/syscalls/fstat64.S
index 1a2281b..6abb146 100644
--- a/libc/arch-x86_64/syscalls/fstat64.S
+++ b/libc/arch-x86_64/syscalls/fstat64.S
@@ -15,5 +15,5 @@
     ret
 END(fstat64)
 
-    .globl _C_LABEL(fstat)
-    .equ _C_LABEL(fstat), _C_LABEL(fstat64)
+    .globl fstat
+    .equ fstat, fstat64