media: atomisp: Fix premature setting of HMM_BO_DEVICE_INITED flag

The HMM_BO_DEVICE_INITED flag was being set in hmm_bo_device_init()
before key initialization steps like kmem_cache_create(),
kmem_cache_alloc(), and __bo_init().

This means that if any of these steps fail, the flag remains set,
misleading other parts of the driver (e.g. hmm_bo_alloc())
into thinking the device is initialized. This could lead
to undefined behavior or invalid memory use.

Additionally, since __bo_init() is called from inside
hmm_bo_device_init() after the flag was already set, its internal
check for HMM_BO_DEVICE_INITED is redundant.

- Move the flag assignment to the end after all allocations succeed.
- Remove redundant check of the flag inside __bo_init()

See the link [1] below for a backtrace which happens when deliberately
triggering the problem of the flag getting set too early.

Link: https://lore.kernel.org/linux-media/CAGn2d8ONZpOHXex8kjeUDgRPiMqKp8vZ=xhGbEDGphV1t7ZEFw@mail.gmail.com/

 [1]
Signed-off-by: Abdelrahman Fekry <abdelrahmanfekry375@gmail.com>
Link: https://lore.kernel.org/r/20250628052536.43737-1-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>