arm64: mm: Simplify __flush_tlb_range_limit_excess()

arm64: mm: Simplify __flush_tlb_range_limit_excess()

__flush_tlb_range_limit_excess() is unnecessarily complicated:

  - It takes a 'start', 'end' and 'pages' argument, whereas it only
    needs 'pages' (which the caller has computed from the other two
    arguments!).

  - It erroneously compares 'pages' with MAX_TLBI_RANGE_PAGES when
    the system doesn't support range-based invalidation but the range to
    be invalidated would result in fewer than MAX_DVM_OPS invalidations.

Simplify the function so that it no longer takes the 'start' and 'end'
arguments and only considers the MAX_TLBI_RANGE_PAGES threshold on
systems that implement range-based invalidation.

Signed-off-by: Will Deacon <will@kernel.org>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>