ARM: arch_timer: include linux/errno.h
ARM: arch_timer: include linux/errno.h

Patch 8a4da6e "arm: arch_timer: move core to drivers/clocksource"
moved a lot of code out of arch_timer.c, but ended up deleting
too much, which broke some configurations.

Obviously, include linux/errno.h is required to return error
values.

Without this patch, building allmodconfig results in:

arch/arm/kernel/arch_timer.c: In function 'arch_timer_sched_clock_init':
arch/arm/kernel/arch_timer.c:55:11: error: 'ENXIO' undeclared (first use in this function)
arch/arm/kernel/arch_timer.c:55:11: note: each undeclared identifier is reported only once for each function it appears in

Signed-off-by: Arnd Bergmann <f2c659f01951776204a6c5b902787d9019fbeebd@arndb.de>
Acked-by: Mark Rutland <1db9dd262beaa64f35756dd39531d9747b7778bb@arm.com>
Cc: Catalin Marinas <15ce75b290ebaf27c3f9fd73ab848685ed3d8261@arm.com>
Cc: Marc Zyngier <a16cc0c82647c52d401177f8e50567df5499e36c@arm.com>

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