drm/tegra: sor: Implement acquire/release for reset

By implementing the acquire/release protocol, the SOR reset can be
shared with other drivers that also adhere to this protocol, such as the
PMC driver that uses the same reset as part of the powergate and -ungate
implementation using generic power domains.

Runtime PM makes sure that the operations are executed in the right
order, and the reset core has error handling and WARNs in place to make
sure the acquire/release protocol is followed.

Signed-off-by: Thierry Reding <treding@nvidia.com>