[CodeGen] Cleanup getVectorShuffle a bit to take advantage of its new ArrayRef argument and its begin/end iterators. Also use 'int' type for number of elements and loop iterators to remove several typecasts. No functional change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@274338 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed