objtool: Add bch2_trans_unlocked_error() to bcachefs noreturns

objtool: Add bch2_trans_unlocked_error() to bcachefs noreturns

Fix the following objtool warning during build time:

    fs/bcachefs/btree_trans_commit.o: warning: objtool: bch2_trans_commit_write_locked.isra.0() falls through to next function do_bch2_trans_commit.isra.0()
    fs/bcachefs/btree_trans_commit.o: warning: objtool: .text: unexpected end of section
......
    fs/bcachefs/btree_update.o: warning: objtool: bch2_trans_update_get_key_cache() falls through to next function flush_new_cached_update()
    fs/bcachefs/btree_update.o: warning: objtool: flush_new_cached_update() falls through to next function bch2_trans_update_by_path()

bch2_trans_unlocked_error() is an Obviously Correct (tm) panic() wrapper,
add it to the list of known noreturns.

[ mingo: Improved the changelog ]

Fixes: fd104e2967b7 ("bcachefs: bch2_trans_verify_not_unlocked()")
Signed-off-by: chenchangcheng <chenchangcheng@kylinos.cn>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20241220074847.3418134-1-ccc194101@163.com