target/m68k: consolidate physical translation offset into get_physical_address()

target/m68k: consolidate physical translation offset into get_physical_address()

Since all callers to get_physical_address() now apply the same page offset to
the translation result, move the logic into get_physical_address() itself to
avoid duplication.

Suggested-by: Philippe Mathieu-Daudé <[email protected]>
Signed-off-by: Mark Cave-Ayland <[email protected]>
Reviewed-by: Laurent Vivier <[email protected]>
Message-Id: <20200701201531[email protected]>
Signed-off-by: Laurent Vivier <[email protected]>