[Hexagon] Adding deallocframe and circular addressing loads.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224869 91177308-0d34-0410-b5e6-96231b3b80d8
[Hexagon] Adding locked loads.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224870 91177308-0d34-0410-b5e6-96231b3b80d8
[Hexagon] Adding auto-incrementing loads with and without byte reversal.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224871 91177308-0d34-0410-b5e6-96231b3b80d8