alarmtimer: Switch to use hrtimer_setup() and hrtimer_setup_on_stack()

hrtimer_setup() and hrtimer_setup_on_stack() take the callback function
pointer as argument and initialize the timer completely.

Replace the hrtimer_init*() variants and the open coded initialization of
hrtimer::function with the new setup mechanism.

Switch to use the new functions.

Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/2bae912336103405adcdab96b88d3ea0353b4228.1730386209.git.namcao@linutronix.de