Remove uses and caches of the target machine and subtarget from
both MSP430InstrInfo and MSP430RegisterInfo. Remove unused member
variable StackAlign from MSP430RegisterInfo. Update constructors
accordingly.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211835 91177308-0d34-0410-b5e6-96231b3b80d8
Move the subtarget dependent features from the target machine to
the subtarget for the MSP430 target.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211836 91177308-0d34-0410-b5e6-96231b3b80d8