Disable ChaCha20 assembly for OPENSSL_X86.

They fail the newly-added in-place tests. Since we don't have bots for them
yet, verified manually that the arm and aarch64 code is fine.

Change-Id: Ic6f4060f63e713e09707af05e6b7736b7b65c5df
Reviewed-on: https://boringssl-review.googlesource.com/7252
Reviewed-by: Adam Langley <agl@google.com>
diff --git a/crypto/chacha/chacha.c b/crypto/chacha/chacha.c
index afe1b2a..870572d 100644
--- a/crypto/chacha/chacha.c
+++ b/crypto/chacha/chacha.c
@@ -25,9 +25,11 @@
   (((uint32_t)((p)[0])) | ((uint32_t)((p)[1]) << 8) | \
    ((uint32_t)((p)[2]) << 16) | ((uint32_t)((p)[3]) << 24))
 
+/* TODO(davidben): Re-enable the ChaCha20 assembly for OPENSSL_X86 once they
+ * pass the in-place tests. */
 #if !defined(OPENSSL_NO_ASM) &&                         \
-    (defined(OPENSSL_X86) || defined(OPENSSL_X86_64) || \
-     defined(OPENSSL_ARM) || defined(OPENSSL_AARCH64))
+    (defined(OPENSSL_X86_64) || defined(OPENSSL_ARM) || \
+     defined(OPENSSL_AARCH64))
 
 /* ChaCha20_ctr32 is defined in asm/chacha-*.pl. */
 void ChaCha20_ctr32(uint8_t *out, const uint8_t *in, size_t in_len,