Revert "tracing: Constify string literal data member in struct trace_event_call"

This reverts commit c5a28af7855586d3da4132687643e681b6ec1e79 which is
commit 452f4b31e3f70a52b97890888eeb9eaa9a87139a upstream.

It breaks the Android kernel abi and can be brought back in the future
in an abi-safe way if it is really needed.

Bug: 161946584
Change-Id: I458b8264fccdb3f99eaf116e9babcaea50e405b3
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h
index bb5252c..2b6ca5b 100644
--- a/include/linux/trace_events.h
+++ b/include/linux/trace_events.h
@@ -346,7 +346,7 @@ struct trace_event_call {
 	struct list_head	list;
 	struct trace_event_class *class;
 	union {
-		const char		*name;
+		char			*name;
 		/* Set TRACE_EVENT_FL_TRACEPOINT flag when using "tp" */
 		struct tracepoint	*tp;
 	};