[mips] The P5600 does not support N32/N64 since it's a 32-bit CPU.

Summary:

Reviewers: atanasyan

Subscribers: cfe-commits, sdardis

Differential Revision: http://reviews.llvm.org/D20963


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@271877 91177308-0d34-0410-b5e6-96231b3b80d8