x86, AMD IOMMU: use true/false instead of 0/1 for bool value

This patch replaces the integer values used for the bool variable in ACPI
scanning code with true and false.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Cc: iommu@lists.linux-foundation.org
Cc: bhavna.sarathy@amd.com
Cc: robert.richter@amd.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>