iommu: No need to set dmar_disabled in check_zero_address()

Before the restructruing of the x86 IOMMU code,
intel_iommu_init() was getting called directly from
pci_iommu_init() and hence needed to explicitly set
dmar_disabled to 1 for the failure conditions of
check_zero_address().

Recent changes don't call intel_iommu_init() if the intel iommu
detection fails as a result of failure in check_zero_address().

So no need for this ifdef and the code inside it.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: yinghai@kernel.org
Cc: youquan.song@intel.com
Cc: joerg.roedel@amd.com
Cc: tony.luck@intel.com
Cc: dwmw2@infradead.org
Link: http://lkml.kernel.org/r/20110824001456.334878686@sbsiddha-desk.sc.intel.com


Signed-off-by: Ingo Molnar <mingo@elte.hu>