get_sname: constify args/return when possible

Signed-off-by: Mike Frysinger <vapier@gentoo.org>

lib/inet.c

@@ -416,7 +416,7 @@ static int read_services(void)
 }
 
 
-char *get_sname(int socknumber, char *proto, int numeric)
+const char *get_sname(int socknumber, const char *proto, int numeric)
 {
     static char buffer[64], init = 0;
     struct service *item;

lib/net-support.h

@@ -124,7 +124,7 @@ extern int ROSE_rinput(int action, int flags, char **argv);
 extern int aftrans_opt(const char *arg);
 extern void aftrans_def(char *tool, char *argv0, char *dflt);
 
-extern char *get_sname(int socknumber, char *proto, int numeric);
+extern const char *get_sname(int socknumber, const char *proto, int numeric);
 
 extern int flag_unx;
 extern int flag_ipx;