ArmVirtPkg: Refactor with PciHostBridgeUtilityLib

ArmVirtPkg: Refactor with PciHostBridgeUtilityLib

Eliminate currently duplicated code in ArmVirtPkg with the common utility
class PciHostBridgeUtilityLib.

BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3059

Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ard Biesheuvel <ard.biesheuvel@arm.com>
Cc: Leif Lindholm <leif@nuviainc.com>
Cc: Sami Mujawar <sami.mujawar@arm.com>
Signed-off-by: Jiahui Cen <cenjiahui@huawei.com>
Signed-off-by: Yubo Miao <miaoyubo@huawei.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Message-Id: <20210119011302.10908-3-cenjiahui@huawei.com>