rs6000, libgcc: Fix up -Wmissing-prototypes warning on rs6000/linux-unwind.h

Jonathan reported and I've verified a
In file included from ../../../libgcc/unwind-dw2.c:412:
./md-unwind-support.h:398:6: warning: no previous prototype for ‘ppc_backchain_fallback’ [-Wmissing-prototypes]
  398 | void ppc_backchain_fallback (struct _Unwind_Context *context, void *a)
      |      ^~~~~~~~~~~~~~~~~~~~~~
warning on powerpc*-linux* libgcc build.

All the other MD_* macro functions are static, so I think the following
is the right thing rather than adding a previous prototype for
ppc_backchain_fallback.

2021-11-10  Jakub Jelinek  <jakub@redhat.com>

	* config/rs6000/linux-unwind.h (ppc_back_fallback): Make it static,
	formatting fix.

diff --git a/libgcc/config/rs6000/linux-unwind.h b/libgcc/config/rs6000/linux-unwind.h
index 8deccc1..4788497 100644 (file)
--- a/libgcc/config/rs6000/linux-unwind.h
+++ b/libgcc/config/rs6000/linux-unwind.h
@@ -395,7 +395,8 @@ struct frame_layout
 };
 
 
-void ppc_backchain_fallback (struct _Unwind_Context *context, void *a)
+static void
+ppc_backchain_fallback (struct _Unwind_Context *context, void *a)
 {
   struct frame_layout *current;
   struct trace_arg *arg = a;