staging: vchiq_arm: Register debugfs after cdev

The commit 2a4d15a4 ("staging: vchiq: Refactor vchiq cdev code")
moved the debugfs directory creation before vchiq character device
registration. In case the latter fails, the debugfs directory won't
be cleaned up.

Fixes: 2a4d15a4 ("staging: vchiq: Refactor vchiq cdev code")
Signed-off-by: Stefan Wahren <wahrenst@gmx.net>
Link: https://lore.kernel.org/r/20250309125014.37166-2-wahrenst@gmx.net


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>