kmsan: allow using __msan_instrument_asm_store() inside runtime

kmsan: allow using __msan_instrument_asm_store() inside runtime

In certain cases (e.g.  when handling a softirq)
__msan_instrument_asm_store(&var, sizeof(var)) may be called with from
within KMSAN runtime, but later the value of @var is used with
!kmsan_in_runtime(), leading to false positives.

Because kmsan_internal_unpoison_memory() doesn't take locks, it should be
fine to call it without kmsan_in_runtime() checks, which fixes the
mentioned false positives.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Alexander Potapenko <[email protected]>
Cc: Dmitry Vyukov <[email protected]>
Cc: Eric Biggers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Marco Elver <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Will Deacon <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>