As with dsb() and isb(), add a __tlbi() helper so that we can avoid
distracting asm boilerplate every time we want a TLBI. As some TLBI
operations take an argument while others do not, some pre-processor is
used to handle these two cases with different assembly blocks.

The existing tlbflush.h code is moved over to use the helper.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
[ rename helper to __tlbi, update comment and commit log ]
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>