add -fvisibility=hidden to CC flags, mark XXX_main functions
EXTERNALLY_VISIBLE. 5% size reduction of libbusybox.so

diff --git a/editors/patch.c b/editors/patch.c
index 65791df..07fa5cf 100644
--- a/editors/patch.c
+++ b/editors/patch.c
@@ -77,7 +77,7 @@
 	return stat(filename, &statbuf);
 }
 
-int patch_main(int argc, char **argv);
+int patch_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int patch_main(int argc, char **argv)
 {
 	int patch_level = -1;