Remove deprecation on int64 type.

I have half a million lines of log-spew in my CI from this and clearly there has been ~no effort in the codebase to actually stop using it. Please do not deprecate such a critical type until at least its own codebase has substantially migrated off of it.

PiperOrigin-RevId: 399093429
Change-Id: I807d9e6c79c4c33f4a50f88ba28fe5fda194ddd4
diff --git a/tensorflow/core/platform/default/integral_types.h b/tensorflow/core/platform/default/integral_types.h
index c54ec12..8feef69 100644
--- a/tensorflow/core/platform/default/integral_types.h
+++ b/tensorflow/core/platform/default/integral_types.h
@@ -26,7 +26,7 @@
 typedef signed char int8;
 typedef short int16;
 typedef int int32;
-[[deprecated("Use int64_t instead.")]] typedef ::std::int64_t int64;
+typedef ::std::int64_t int64;
 
 typedef unsigned char uint8;
 typedef unsigned short uint16;