nfsd: select CONFIG_PROC_FS in nfsv4 and gss server cases

The server depends on upcalls under /proc to support nfsv4 and gss.
Acked-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

fs/Kconfig

@@ -1674,6 +1674,8 @@ config NFSD
 	select CRYPTO_MD5 if NFSD_V4
 	select CRYPTO if NFSD_V4
 	select FS_POSIX_ACL if NFSD_V4
+	select PROC_FS if NFSD_V4
+	select PROC_FS if SUNRPC_GSS
 	help
 	  If you want your Linux box to act as an NFS *server*, so that other
 	  computers on your local network which support NFS can access certain