firmware: tegra: Use in-band messages for firmware version query

Add support for a new MRQ, that uses in-band messaging instead of IOVA
buffer, to retrieve the firmware version 'tag' during boot. If an
older firmware is used, that does not support the new MRQ, fall back
to the earlier implementation.

Signed-off-by: Timo Alho <talho@nvidia.com>
Acked-by: Sivaram Nair <sivaramn@nvidia.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>