Mark the C version of md5_block_data_order static.

This doesn't really matter, but once less visible symbol.

Change-Id: If4ee8cfe5c9db9d1c05ca74b8c6fee5cf3ea5a9b
Reviewed-on: https://boringssl-review.googlesource.com/31764
Reviewed-by: Adam Langley <agl@google.com>
diff --git a/crypto/fipsmodule/md5/md5.c b/crypto/fipsmodule/md5/md5.c
index a04801e..370b42a 100644
--- a/crypto/fipsmodule/md5/md5.c
+++ b/crypto/fipsmodule/md5/md5.c
@@ -85,11 +85,14 @@
     (defined(OPENSSL_X86_64) || defined(OPENSSL_X86))
 #define MD5_ASM
 #define md5_block_data_order md5_block_asm_data_order
+extern void md5_block_data_order(uint32_t *state, const uint8_t *data,
+                                 size_t num);
+#else
+static void md5_block_data_order(uint32_t *state, const uint8_t *data,
+                                 size_t num);
 #endif
 
 
-void md5_block_data_order(uint32_t *state, const uint8_t *data, size_t num);
-
 #define DATA_ORDER_IS_LITTLE_ENDIAN
 
 #define HASH_CTX MD5_CTX
@@ -155,7 +158,8 @@
 #ifdef X
 #undef X
 #endif
-void md5_block_data_order(uint32_t *state, const uint8_t *data, size_t num) {
+static void md5_block_data_order(uint32_t *state, const uint8_t *data,
+                                 size_t num) {
   uint32_t A, B, C, D, l;
   uint32_t XX0, XX1, XX2, XX3, XX4, XX5, XX6, XX7, XX8, XX9, XX10, XX11, XX12,
       XX13, XX14, XX15;