Canonicalize implicit deduction guide parameter types when forming a deduction

Canonicalize implicit deduction guide parameter types when forming a deduction
guide from a constructor.

The purpose of this change is to avoid triggering instantiation of the class
when substituting back into the deduction guide if it uses a typedef member.
We will still instantiate the class if the constructor (explicitly or
implicitly, directly or indirectly) uses the current instantiation in a way
that we can't canonicalize out, but that seems unavoidable.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@295016 91177308-0d34-0410-b5e6-96231b3b80d8