[Statepoints] Fix overalignment of loads in no-realign-stack functions

This really should have been part of 366765.  For some reason, I forgot to handle the corresponding load side, and the readable test cases (using deopt vs statepoints) turned out to be overly reduced.  Oops.

As seen in the test change, the problem was that we were using a load with alignment expectations rather than the unaligned variant when the stack alignment was less than that prefered type alignment.

llvm-svn: 367718