KVM: selftests: Fix spelling mistake "trigged" -> "triggered"

There are spelling mistakes in __GUEST_ASSERT messages. Fix them.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Acked-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Anup Patel <anup@brainfault.org>
Link: https://lore.kernel.org/r/20240307081951.1954830-1-colin.i.king@gmail.com