[Mips] Simplify the code. Replace redundant 'switch' operator by the single 'if' one.
[Mips] Simplify the code. Replace redundant 'switch' operator by the single 'if' one.

git-svn-id: f6089bf0e6284f307027cef4f64114ee9ebb0424@201131 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/lld,llvm-mirror/lld