media: atomisp: Remove debug sysfs attributes active_bo and free_bo

The sysfs attributes active_bo and free_bo expose internal buffer
state used only for debugging purposes. These are not part of
any standard kernel ABI, and need to be removed before this
driver may be moved out of drivers/staging.

- Remove active_bo and free_bo attributes
- Remove group registration calls form hmm_init() and hmm_cleanup()

Suggested-by: Hans de Goede <hansg@kernel.org>
Signed-off-by: Abdelrahman Fekry <abdelrahmanfekry375@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/r/20250627100604.29061-1-abdelrahmanfekry375@gmail.com


Reviewed-by: Hans de Goede <hansg@kernel.org>
Signed-off-by: Hans de Goede <hansg@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>