MIPS: Only include the platform file needed

Instead of including all Platform files, we simply include the
needed one and avoid clashes with makefile variables.

Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS: add support for SGI Octane (IP30)

This changeset adds support for SGI Octane/Octane2 workstations.

Signed-off-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
Signed-off-by: Paul Burton <paulburton@kernel.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org