gccrs: [E0164] Neither tuple struct nor tuple variant used as a pattern

gccrs: [E0164] Neither tuple struct nor tuple variant used as a pattern

Checking if pattern has items, before returing solves ICE.
Added error code and rich location.
Also, fixes https://github.com/Rust-GCC/gccrs/issues/2430

gcc/rust/ChangeLog:

	* ast/rust-pattern.h: No need of assertion, we are handling it.
	* resolve/rust-early-name-resolver.cc (EarlyNameResolver::visit):
	Added check which emits error instead of using assertion.
	* typecheck/rust-hir-type-check-pattern.cc (TypeCheckPattern::visit):
	Added rich location and error code.

gcc/testsuite/ChangeLog:

	* rust/compile/match5.rs:
	Updated comment for dejagnu.
	* rust/compile/pattern-struct.rs: New test for ICE.

Signed-off-by: Muhammad Mahad <mahadtxt@gmail.com>