Rename asn1_locl.h to internal.h.

Match the other internal headers.

Change-Id: I1b8e995b9a59fa02a7e38ee0ec9141e15655071a
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/48325
Reviewed-by: Adam Langley <agl@google.com>
diff --git a/crypto/asn1/tasn_new.c b/crypto/asn1/tasn_new.c
index dc864da..540ed8f 100644
--- a/crypto/asn1/tasn_new.c
+++ b/crypto/asn1/tasn_new.c
@@ -63,7 +63,7 @@
 #include <openssl/mem.h>
 #include <openssl/obj.h>
 
-#include "asn1_locl.h"
+#include "internal.h"
 #include "../internal.h"