[OpenCL] Fix overloading resolution of addrspace constructors
This fixes the prioritization of address spaces when choosing a
constructor, stopping them from being considered equally good,
which made the construction of types that could be constructed
by more than one of the constructors.
It does this by preferring the most specific address space,
which is decided by seeing if one of the address spaces is
a superset of the other, and preferring the other.
Fixes: PR50329
Reviewed By: Anastasia
Differential Revision: https://reviews.llvm.org/
D102850