gccrs: Support fully qualified calls to trait items from CallExpr's

gccrs: Support fully qualified calls to trait items from CallExpr's

Fixes #2070

gcc/rust/ChangeLog:

	* backend/rust-compile-resolve-path.cc (HIRCompileBase::query_compile):
	reuse resolve_method_address to monomorphize the call if required
	* typecheck/rust-hir-type-check-path.cc (TypeCheckExpr::resolve_segments):
	allow matching against unimplemented trait item bounds

gcc/testsuite/ChangeLog:

	* rust/compile/issue-2070.rs: New test.

Signed-off-by: Philip Herron <herron.philip@googlemail.com>