Firmware still not loaded when resuming device

If one tries to, for example, write to /sys/devices/platform/soc@0/5000000.gpu/power/autosuspend_delay_ms right after boot, the runtime PM core will try to resume the device but that will fail because the firmware is loaded only when the first client connects.

https://gitlab.freedesktop.org/mesa/mesa/-/jobs/10106611#L1405

Furthermore, the device is left in an inconsistent state and the GPU is unusable until the next reboot.