Inside the calling convention logic LocVT is always a simple

Inside the calling convention logic LocVT is always a simple
value type, so there is no point in passing it around using
an EVT.  Use the simpler MVT everywhere.  Rather than trying
to propagate this information maximally in all the code that
using the calling convention stuff, I chose to do a mainly
low impact change instead.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118167 91177308-0d34-0410-b5e6-96231b3b80d8