tests: kernel: move the direct interrupt test to arch testing

Move the direct interrupt test to tests/arch/x86/direct_isr. Two
reasons:
1. The direct interrupt is only for x86. It's arch-specific.
2. And it need extra gcc option to pass the build, that will
include testsuite number. Although it seems like we add a
extra testsuite for it, actually we can reduce whole tests
configuration in tests/kernel/interrupt. And also make this
test more generic as it used to be.

Signed-off-by: Enjia Mai <enjia.mai@intel.com>