[mips][microMIPS] Extending size reduction pass with ADDIUSP and ADDIUR1SP

[mips][microMIPS] Extending size reduction pass with ADDIUSP and ADDIUR1SP
Author: milena.vujosevic.janicic
Reviewers: sdardis
The patch extends size reduction pass for MicroMIPS.
The following instructions are examined and transformed, if possible:
ADDIU instruction is transformed into 16-bit instruction ADDIUSP
ADDIU instruction is transformed into 16-bit instruction ADDIUR1SP
Function InRange is changed to avoid left shifting of negative values, since
that caused some sanitizer tests to fail (so the previous patch
Differential Revision: https://reviews.llvm.org/D34511

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@308011 91177308-0d34-0410-b5e6-96231b3b80d8