MIPS: mm: Move UNIQUE_ENTRYHI macro to a header file

MIPS: mm: Move UNIQUE_ENTRYHI macro to a header file

The UNIQUE_ENTRYHI definition was duplicated whenever there
was the need to flush the TLB entries. We move this common
definition to a header file.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Signed-off-by: John Crispin <blogic@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/6129/