[OpenCL] Defer addr space deduction for dependent type.

This patch removes deduction of address spaces in parsing
for types that depend on template parameter even if an
address space is already known. Deducing it early interferes
with template instantiation/specialization logic that uses
source address space where address space is not present.

Address space deduction for templates is therefore fully
moved to the template instantiation/specialization phase.

Patch by Ole Strohm (olestrohm)!

Tags: #clang

Differential Revision: https://reviews.llvm.org/D82781