iommu/arm-smmu: Fix DOMAIN_ATTR_PAGE_TABLE_FORCE_COHERENT enablement

The functionality provided by DOMAIN_ATTR_PAGE_TABLE_FORCE_COHERENT
can be guaranteed, independent of CONFIG_QCOM_IOMMU_IO_PGTABLE_QUIRKS,
so do not guard its enablement with that config.

Change-Id: Ifae4280f256b99529ae5a074dbc91b37b5d87e21
Signed-off-by: Isaac J. Manjarres <isaacm@codeaurora.org>