vmem: vmem block funcs now able to lazy init devices

[edvardxyz]

Lazy init if vmem_block_init() not called by user

[Copilot]

Pull request overview

Adds lazy initialization of VMEM block devices so that cache read/write/flush operations will trigger device initialization if vmem_block_init() has not been called by the user. The per-device init/print logic is also factored out of vmem_block_init() into a new static helper _vmem_block_init().

Changes:

• New _vmem_block_init() static helper that prints device info and invokes the device's init callback.
• cache_flush, cache_write, and cache_read now check drv->device->state == VMEM_BLOCK_STATE_UNKNOWN and call _vmem_block_init() to lazily initialize the device.
• vmem_block_init() is refactored to call _vmem_block_init() per device and logs an error when initialization fails.

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[Copilot]

Pull request overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated 2 comments.