qemu-mips: Cleanup whitespace, indentation, etc.

No functional change.

This patch was originally submitted by Jean-Christophe PLAGNIOL-VILLARD.
Then I re-created from scratch, and changed more lines than the original.

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Shinya Kuribayashi <skuribay@ruby.dti.ne.jp>