clocksource/drivers/sp804: Do not use timer namespace for timer_shutdown() function

clocksource/drivers/sp804: Do not use timer namespace for timer_shutdown() function

A new "shutdown" timer state is being added to the generic timer code. One
of the functions to change the timer into the state is called
"timer_shutdown()". This means that there can not be other functions
called "timer_shutdown()" as the timer code owns the "timer_*" name space.

Rename timer_shutdown() to evt_timer_shutdown() to avoid this conflict.

Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Link: https://lkml.kernel.org/r/20221106212702.182883323@goodmis.org
Link: https://lore.kernel.org/all/20221105060155.592778858@goodmis.org/
Link: https://lore.kernel.org/r/20221110064147.158230501@goodmis.org
Link: https://lore.kernel.org/r/20221123201624.634354813@linutronix.de