Make GetRSDPEFI and GetRSDPMem functions public
Make GetRSDPEFI and GetRSDPMem functions public

This allows you to select which method to use for finding the RSDP.

Signed-off-by: Ryan O'Leary <32139beaa9c574695821e85473b09a4e33316467@google.com>

u-root/u-root,hugelgupf/u-root,hugelgupf/u-root,u-root/u-root,hugelgupf/u-root,hugelgupf/u-root,u-root/u-root