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

diff --git a/networking/wget.c b/networking/wget.c
index 3f9954c..b12d19a 100644
--- a/networking/wget.c
+++ b/networking/wget.c
@@ -391,7 +391,7 @@
 }
 
 
-int wget_main(int argc, char **argv);
+int wget_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int wget_main(int argc, char **argv)
 {
 	char buf[512];