drm/msm/a6xx: Print GMU core firmware version at boot

Log the version for informational purposes, such as for keeping track
of possible GMU fw-related failures in crash / CI logs.

Intentionally not implemented on the if (gmu->legacy) codepath, as
these registers seem not to be used on there.

Downstream additionally warns if the firmware version is too old for
a given GPU, but we already pair the binary to a given GPU, so let's
not go there at the moment.

Signed-off-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Reviewed-by: Akhil P Oommen <quic_akhilpo@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/629934/


Signed-off-by: Rob Clark <robdclark@chromium.org>