[Mips][msa] Added the simple builtins (add_a to dpsub[su], ilvev to ldi)

Includes:
add_a, adds_[asu], addv, addvi, andi.b, asub_[su].[bhwd], aver?_[su]_[bhwd],
bclr, bclri, bins[lr], bins[lr]i, bmnzi, bmzi, bneg, bnegi, bseli, bset, bseti,
c(eq|ne), c(eq|ne)i, cl[et]_[su], cl[et]i_[su], copy_[su].[bhw], div_[su],
dotp_[su], dpadd_[su], dpsub_[su], ilvev, ilvl, ilvod, ilvr, insv, insve,
ldi

Patch by Daniel Sanders


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188457 91177308-0d34-0410-b5e6-96231b3b80d8