[mips][microMIPS] Implement DPS.W.PH, DPSQ_S.W.PH, DPSQ_SA.L.W, DPSQX_S.W.PH,...

[mips][microMIPS] Implement DPS.W.PH, DPSQ_S.W.PH, DPSQ_SA.L.W, DPSQX_S.W.PH, DPSQX_SA.W.PH, DPSU.H.QBL, DPSU.H.QBR and DPSX.W.PH instructions
Differential Revision: http://reviews.llvm.org/D14058

llvm-svn: 253443