cpumask: Add a x86-specific cpumask_clear_cpu() helper

Add a x86-specific cpumask_clear_cpu() helper which will be used in
places where the explicit KASAN-instrumentation in the *_bit() helpers
is unwanted.

Also, always inline two more cpumask generic helpers.

allyesconfig:

     text    data     bss     dec     hex filename
  190553143       159425889       32076404        382055436       16c5b40c vmlinux.before
  190551812       159424945       32076404        382053161       16c5ab29 vmlinux.after

Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Marco Elver <elver@google.com>
Link: https://lore.kernel.org/r/20220204083015.17317-2-bp@alien8.de