gas/

gas/
	* read.c [HANDLE_BUNDLE] (bundle_lock_depth): New variable.
	(read_a_source_file) [HANDLE_BUNDLE]: Reset it.
	[HANDLE_BUNDLE] (s_bundle_lock, s_bundle_unlock): Allow nested
	pairs.

gas/testsuite/
	* gas/i386/bundle-bad.s: Remove nested .bundle_lock case.
	* gas/i386/bundle-bad.l: Remove expected error line.
	* gas/i386/bundle-lock.s: Add nested .bundle_lock case.
	* gas/i386/bundle-lock.d: Update expectations.