[flang][OpenACC] Resolve associations before testing declare flags (#221346)

The OpenACC declare flags are set by semantics on a single symbol: the
one resolved in the scope containing the !$acc declare directive. Any
other scope naming the same entity reaches it through an association
symbol, and those symbols carry their own, empty flag sets.
The allocate and deallocate action helpers tested the symbol taken
straight from the ALLOCATE or DEALLOCATE statement. For an allocatable
declared in a host scope and allocated in an internal subprogram the
AccDeclare test
therefore failed, no acc.declare_action attribute was attached, and
ACCDeclareActionConversion had nothing to convert. The emitted recipes
were never called, so the device copy was neither created on allocation
nor deleted on deallocation.
Resolve to the ultimate symbol and pass it on. Forwarding the resolved
symbol is required because the deallocation attach helpers independently
re-test the data clause flags.
This matches the rest of the OpenACC lowering, which already resolves
before reading these flags. Recipe names are unaffected because
mangleName resolves associations itself before mangling.

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Co-authored-by: Yebin Chon <ychon@nvidia.com>