Fix warning on uninitialized buftype

Pointed out by coverity analyzer.  resp_buftype is
not initialized in one path which can rarely log
a spurious warning (buf is null so there will
not be a problem with freeing data, but if buf_type
were randomly set to wrong value could log a warning)

Reported by Coverity (CID 1269144)

Signed-off-by: Steve French <smfrench@gmail.com>
Acked-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Acked-by: Sachin Prabhu <sprabhu@redhat.com>
Reviewed-by: Jeff Layton <jlayton@poochiereds.net>
diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 3417340..1b906de 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -2114,7 +2114,7 @@
 	struct kvec iov[2];
 	int rc = 0;
 	int len;
-	int resp_buftype;
+	int resp_buftype = CIFS_NO_BUFFER;
 	unsigned char *bufptr;
 	struct TCP_Server_Info *server;
 	struct cifs_ses *ses = tcon->ses;