posix-cpu-timers: Move prof/virt_ticks into caller

The functions have only one caller left. No point in having them.

Move the almost duplicated code into the caller and simplify it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192920.729298382@linutronix.de