[GlobalISel] Fix assert failure when legalizing non-power-2 loads.

Until we support extending loads properly we're going to fall back for these.
We already handle stores in the same way, so this is just being consistent.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@324001 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed