Add a firmware module to load, parse, and map the MCU firmware sections
into shared GEM memory at the required virtual addresses accessible by the
GPU.

Create a firmware instance during probe and store it inside the
TyrDrmRegistrationData to keep it alive after probe. Use the firmware
instance to boot the MCU.

Remove the dead-code annotations from the MMU, VM, slot manager, and
kernel BO code now that these paths are used by the firmware module.

Update Kconfig to add the RUST_FW_LOADER_ABSTRACTIONS dependency
required by this module.

Co-developed-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Deborah Brouwer <deborah.brouwer@collabora.com>
Link: https://patch.msgid.link/20260728-fw-boot-b4-v10-7-9187aefa3f2f@collabora.com
Signed-off-by: Alice Ryhl <aliceryhl@google.com>

Add GPU virtual address space management using the DRM GPUVM framework.
Each virtual memory (VM) space is backed by ARM64 LPAE Stage 1 page tables
and can be mapped into hardware address space (AS) slots for GPU execution.

The implementation provides memory isolation and virtual address
allocation. VMs support mapping GEM buffer objects with configurable
protection flags (readonly, noexec, uncached) and handle both 4KB and 2MB
page sizes. A new_dummy_object() helper is provided to create a dummy GEM
object for use as a GPUVM root.

The vm module integrates with the MMU for address space activation and
provides map/unmap/remap operations with page table synchronization.

Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Co-developed-by: Daniel Almeida <daniel.almeida@collabora.com>
Signed-off-by: Daniel Almeida <daniel.almeida@collabora.com>
Co-developed-by: Deborah Brouwer <deborah.brouwer@collabora.com>
Signed-off-by: Deborah Brouwer <deborah.brouwer@collabora.com>
Link: https://patch.msgid.link/20260728-fw-boot-b4-v10-4-9187aefa3f2f@collabora.com
[aliceryhl: fix integer cast on 32-bit arm]
Signed-off-by: Alice Ryhl <aliceryhl@google.com>