[Mips] Factor out the code assign a value to the absolute atom into the separate function.
[Mips] Factor out the code assign a value to the absolute atom into the
separate function.

git-svn-id: f6089bf0e6284f307027cef4f64114ee9ebb0424@209593 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/lld,llvm-mirror/lld