Canonicalize mips conditional move patterns.

Canonicalize mips conditional move patterns.

* config/mips/mips.c (gen_conditional_move): Use GET_MODE (op0) instead
of VOIDmode for comparison code mode.
* config/mips/mips.md: For conditional move patterns, use mode of
first compare operand for comparison mode, instead of VOIDmode.

From-SVN: r86145