9p: Allow building 9p with user namespaces enabled.
9p: Allow building 9p with user namespaces enabled.

Now that the uid_t -> kuid_t, gid_t -> kgid_t conversion
has been completed in 9p allow 9p to be built when user
namespaces are enabled.

Cc: Eric Van Hensbergen <f6aaec02cb2023b586fda1596c965a5752b892b4@gmail.com>
Cc: Ron Minnich <f569d0af9a3481c4007b95c7180d6c41009f2513@gmail.com>
Cc: Latchesar Ionkov <1cce15653918254946894aae1b185a0680390953@ionkov.net>
Signed-off-by: "Eric W. Biederman" <8a741aa8cbd77ebc4a56ddb528ce9fd15d42f034@xmission.com>

KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas