kasan, arm64: tests supports for HW_TAGS async mode

This change adds KASAN-KUnit tests support for the async HW_TAGS mode.

In async mode, tag fault aren't being generated synchronously when a
bad access happens, but are instead explicitly checked for by the kernel.

As each KASAN-KUnit test expect a fault to happen before the test is over,
check for faults as a part of the test handler.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Andrey Konovalov <andreyknvl@google.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://lore.kernel.org/r/20210315132019.33202-10-vincenzo.frascino@arm.com


Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>