[PATCH] ethdev: add dev_private check for secondary process

[Khadem Ullah]

Yes, I think this can be addressed at both the PMD and ethdev layers.  
To centralize the logic and avoid duplication across drivers, I’ve also submitted 
a patch at the ethdev layer that checks for `dev_private` accessibility 
in the secondary process context.

Please see the updated patch here:  
https://patches.dpdk.org/project/dpdk/patch/20250722115439.1353573-1-14pwcse1224@uetpeshawar.edu.pk/

Looking forward to your feedback.

Best Regards, 
Khadem Ullah