The rework of the posix-cpu-timers patch series dropped the empty
declaration of struct cpu_timer for the CONFIG_POSIX_TIMERS=n case which
causes the build to fail:
./include/linux/posix-timers.h:218:20: error: field 'cpu' has incomplete type
Add it back.
Fixes: 60bda037f1dd ("posix-cpu-timers: Utilize timerqueue for storage") Reported-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>