fs/9p/v9fs.c: fix spelling mistake "Uknown" -> "Unknown"

fix spelling mistake in pr_info message text

Link: http://lkml.kernel.org/r/20180526150650.10562-1-colin.king@canonical.com
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>

fs/9p/v9fs.c

@@ -343,7 +343,7 @@ static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
 				v9ses->uid = make_kuid(current_user_ns(), uid);
 				if (!uid_valid(v9ses->uid)) {
 					ret = -EINVAL;
-					pr_info("Uknown uid %s\n", s);
+					pr_info("Unknown uid %s\n", s);
 				}
 			}