drm/imagination: Fixed missing header in pvr_fw_meta

A missing header causes the compiler to warn that the function below is not
forward declared.

>> drivers/gpu/drm/imagination/pvr_fw_meta.c:33:1: warning: no previous prototype for function 'pvr_meta_cr_read32' [-Wmissing-prototypes]
33 | pvr_meta_cr_read32(struct pvr_device *pvr_dev, u32 reg_addr, u32 *reg_value_out)
| ^
drivers/gpu/drm/imagination/pvr_fw_meta.c:32:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
32 | int
| ^
| static
1 warning generated.

Include the correct header.

Reported-by: Arnd Bergmann <arnd@arndb.de>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202311250226.Da2yiSKp-lkp@intel.com/
Fixes: cc1aeedb98ad ("drm/imagination: Implement firmware infrastructure and META FW support")
Signed-off-by: Donald Robson <donald.robson@imgtec.com>
Signed-off-by: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20231130160017.259902-2-donald.robson@imgtec.com

drm/imagination: Implement firmware infrastructure and META FW support

The infrastructure includes parsing of the firmware image, initialising
FW-side structures, handling the kernel and firmware command
ringbuffers and starting & stopping the firmware processor.

This patch also adds the necessary support code for the META firmware
processor.

Changes since v8:
- Fix documentation for pvr_fwccb_process()
- Corrected license identifiers

Changes since v6:
- Add a minimum retry count to pvr_kccb_reserve_slot_sync()

Changes since v5:
- Add workaround for BRN 71242
- Attempt to recover GPU on MMU flush command failure

Changes since v4:
- Remove use of drm_gem_shmem_get_pages()
- Remove interrupt resource name

Changes since v3:
- Hard reset FW processor on watchdog timeout
- Switch to threaded IRQ
- Rework FW object creation/initialisation to aid hard reset
- Added MODULE_FIRMWARE()
- Use drm_dev_{enter,exit}

Signed-off-by: Sarah Walker <sarah.walker@imgtec.com>
Signed-off-by: Donald Robson <donald.robson@imgtec.com>
Link: https://lore.kernel.org/r/bb52a8dc84f296b37dc6668dfe8fbaf2ba551139.1700668843.git.donald.robson@imgtec.com
Signed-off-by: Maxime Ripard <mripard@kernel.org>