iommu/vt-d: Remove unused extern declaration dmar_parse_dev_scope()

Since commit 2e455289 ("iommu/vt-d: Unify the way to process DMAR
device scope array") this is not used anymore, so can remove it.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20230802133934.19712-1-yuehaibing@huawei.com


Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>