fs/proc/namespaces.c: prevent crash when ns_entries[] is empty
fs/proc/namespaces.c: prevent crash when ns_entries[] is empty

If CONFIG_NET_NS, CONFIG_UTS_NS and CONFIG_IPC_NS are disabled,
ns_entries[] becomes empty and things like
ns_entries[ARRAY_SIZE(ns_entries) - 1] will explode.

Reported-by: Richard Weinberger <320bca71fc381a4a025636043ca86e734e31cf8b@nod.at>
Cc: "Eric W. Biederman" <8a741aa8cbd77ebc4a56ddb528ce9fd15d42f034@xmission.com>
Cc: Daniel Lezcano <e9fa45941f2ebe89c1b9d6c5f339ab42eadb8567@free.fr>
Signed-off-by: Andrew Morton <5c1e68b099950c134891f0b6e179498a8ebe9cf9@linux-foundation.org>
Signed-off-by: Linus Torvalds <69652caca27c8b940640ad396ab71f93cacec34f@linux-foundation.org>

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