Another fix for the regenerated chacha_vec_arm.S.

I put the header back, but missed the #endif at the end of the file.
Regenerating this is clearly too error prone – I'll write a script to do
it for the future.

Change-Id: I06968c9f7a4673f5942725e727c67cb4e01d361a
diff --git a/crypto/chacha/chacha_vec_arm.S b/crypto/chacha/chacha_vec_arm.S
index 7a4dd5a..130be78 100644
--- a/crypto/chacha/chacha_vec_arm.S
+++ b/crypto/chacha/chacha_vec_arm.S
@@ -1421,3 +1421,5 @@
 	.word	1797285236
 	.ident	"GCC: (Linaro GCC 2014.11) 4.9.3 20141031 (prerelease)"
 	.section	.note.GNU-stack,"",%progbits
+
+#endif  /* !OPENSSL_NO_ASM */