OvmfPkg: AcpiPlatformDxe: exclude RSD PTR from QEMU's fw_cfg payload

OvmfPkg: AcpiPlatformDxe: exclude RSD PTR from QEMU's fw_cfg payload

In one of the next patches we'll start scanning all fw_cfg files that QEMU
advertises as carrying ACPI tables, not just "etc/acpi/tables".

The RSD PTR table is known to occur in the "etc/acpi/rsdp" fw_cfg file.
Since edk2 handles RSD PTR automatically, similarly to RSDT and XSDT,
let's exclude RSD PTR too from the manually installed tables.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@15573 6f19259b-4bc3-4df7-8a09-765794883524