SUNRPC: Clean up svc_find_xprt() calling sequence

Clean up: add documentating comment and use appropriate data types for
svc_find_xprt()'s arguments.

This also eliminates a mixed sign comparison: @port was an int, while
the return value of svc_xprt_local_port() is an unsigned short.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/include/linux/sunrpc/svc_xprt.h b/include/linux/sunrpc/svc_xprt.h
index 959b931..55b6858 100644
--- a/include/linux/sunrpc/svc_xprt.h
+++ b/include/linux/sunrpc/svc_xprt.h
@@ -80,7 +80,8 @@
 void	svc_delete_xprt(struct svc_xprt *xprt);
 int	svc_port_is_privileged(struct sockaddr *sin);
 int	svc_print_xprts(char *buf, int maxlen);
-struct	svc_xprt *svc_find_xprt(struct svc_serv *, char *, int, int);
+struct	svc_xprt *svc_find_xprt(struct svc_serv *serv, const char *xcl_name,
+			const sa_family_t af, const unsigned short port);
 int	svc_xprt_names(struct svc_serv *serv, char *buf, int buflen);
 
 static inline void svc_xprt_get(struct svc_xprt *xprt)