uml: fix mconsole stop
uml: fix mconsole stop

Bring back the functionality of stopping user mode linux with the help of
mconsole.

[jdike - the bug being fixed is that the mconsole file descriptor is already
set O_NONBLOCK or not, depending on whether we want no blocking (the normal
case) or we want blocking (when an mconsole stop is in effect), so the
MSG_DONTWAIT is redundant in the normal case, and wrong when we want to
block.]

Signed-off-by: Karol Swietlicki <6e03174844f1e04ed517bc3ad5fbe5f406b41f85@gmail.com>
Signed-off-by: Jeff Dike <f9b6309e85863eba5d28138b6a0f35841ce976d0@linux.intel.com>
Signed-off-by: Andrew Morton <5c1e68b099950c134891f0b6e179498a8ebe9cf9@linux-foundation.org>
Signed-off-by: Linus Torvalds <69652caca27c8b940640ad396ab71f93cacec34f@linux-foundation.org>

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