Add run-pass case for issue #14308

Enum wildcard patterns in match behave wrong when applied to tuple
structs. They either ICE or cause an LLVM error.
Fix ICE regarding tuple struct matches using (..)

Fixes half of #14308.
Fix LLVM error with tuple struct match using (..)

Consider PatEnums constructed with A(..) to be candidates for tuple
struct patterns, not just ones constructed with A(a,b,c). If these
patterns shouldn't be valid tuple struct patterns (as they're equivalent
to _), this needs to be caught before we get to trans.

Fixes #14308.
auto merge of #14313 : kballard/rust/tuple_dotdot_match_ice, r=cmr

Fixes #14308.