gccrs: Fix rust breakage with nr2

gccrs: Fix rust breakage with nr2

Nr2 did not emit the correct error message for break identifier "rust".

gcc/rust/ChangeLog:

	* resolve/rust-late-name-resolver-2.0.cc (Late::visit): Add "rust"
	identifier detection akin to nr1.
	(funny_ice_finalizer): Copy ICE finalizer from nr1.
	* resolve/rust-late-name-resolver-2.0.h: Add funny_error member
	context state.
	* Make-lang.in: Add new translation unit for new ice finalizer.
	* resolve/rust-ast-resolve-expr.cc: Move ice
	finalizer to it's own file.
	* resolve/rust-ice-finalizer.cc: New file.
	* resolve/rust-ice-finalizer.h: New file.

gcc/testsuite/ChangeLog:

	* rust/compile/nr2/exclude: Remove break-rust3.rs from exclude list.

Signed-off-by: Pierre-Emmanuel Patry <pierre-emmanuel.patry@embecosm.com>