Fix nearly all compilation warnings under Apple gcc-4.0.  Tested with OPT="-g
-Wall -Wstrict-prototypes -Werror" in both --with-pydebug mode and --without.
There's still a batch of non-prototype warnings in Xlib.h that I don't know how
to fix.
diff --git a/Modules/_ssl.c b/Modules/_ssl.c
index 4b0958a..643693e 100644
--- a/Modules/_ssl.c
+++ b/Modules/_ssl.c
@@ -667,7 +667,7 @@
 	char buf[2048];
 	char *vptr;
 	int len;
-	const unsigned char *p;
+	unsigned char *p;
 
 	if (certificate == NULL)
 		return peer_alt_names;