bpf: fs/xattr: don't assume the inode is locked in path_unlink/path_rmdir

bpf_lsm_has_d_inode_locked() makes the verifier rewrite
bpf_[set|remove]_dentry_xattr() to the _locked variants, which assume
that the caller already holds the inode's i_rwsem.  The path_unlink and
path_rmdir hooks are listed, but security_path_unlink() and
security_path_rmdir() run before vfs_unlink()/vfs_rmdir() take the
victim inode's i_rwsem, so a sleepable BPF LSM program attached to
either hook mutates the victim's xattrs without the lock held.

Drop the two path hooks from d_inode_locked_hooks so that the verifier
keeps the locking bpf_[set|remove]_dentry_xattr() variants, which take
the lock themselves.

Fixes: 56467292794b8 ("bpf: fs/xattr: Add BPF kfuncs to set and remove xattrs")
Cc: stable@vger.kernel.org
Signed-off-by: Andrea Parri <parri.andrea@gmail.com>
Link: https://patch.msgid.link/20260922145530.369775-1-parri.andrea@gmail.com
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>