x86/nmi: Remove export of local_touch_nmi()

x86/nmi: Remove export of local_touch_nmi()

Commit:

  feb6cd6a0f9f ("thermal/intel_powerclamp: stop sched tick in forced idle")

got rid of the last exported user of local_touch_nmi() a while back.

Remove the unnecessary export.

Signed-off-by: Sohil Mehta <sohil.mehta@intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Kai Huang <kai.huang@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Nikolay Borisov <nik.borisov@suse.com>
Link: https://lore.kernel.org/r/20250327234629.3953536-5-sohil.mehta@intel.com