linux-yocto: add qemumips64 compatibility

linux-yocto: add qemumips64 compatibility

The 3.8 and linux-yocto-dev kernel trees carry qemumips64 support. Adding
the board to the compatibility directly in the recipes is the first step
to adding mips64 support to the broader set of packages.

(From OE-Core rev: 0b4187fac16f78a1f9ba1c696edbc8c2aa189cb1)

Signed-off-by: Bruce Ashfield <bruce.ashfield@windriver.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>
Signed-off-by: Saul Wold <sgw@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>