Add a bunch more missing ENDs to assembler routines.

This isn't everything; I've missed out those x86 files that are

Change-Id: Idb7bb1a68796d6c0b70ea2b5c3300e49da6c62d2
diff --git a/libc/arch-x86/string/strcpy.S b/libc/arch-x86/string/strcpy.S
index 341eb6c..7d9b87e 100644
--- a/libc/arch-x86/string/strcpy.S
+++ b/libc/arch-x86/string/strcpy.S
@@ -61,3 +61,4 @@
 	jnz	L1
 L2:	popl	%eax			/* pop dst address */
 	ret
+END(strcpy)