kasan: add bug reporting routines for tag-based mode

This commit adds rountines, that print tag-based KASAN error reports.
Those are quite similar to generic KASAN, the difference is:

1. The way tag-based KASAN finds the first bad shadow cell (with a
   mismatching tag). Tag-based KASAN compares memory tags from the shadow
   memory to the pointer tag.

2. Tag-based KASAN reports all bugs with the "KASAN: invalid-access"
   header.

Also simplify generic KASAN find_first_bad_addr.

Link: http://lkml.kernel.org/r/aee6897b1bd077732a315fd84c6b4f234dbfdfcb.1544099024.git.andreyknvl@google.com


Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>