media: venus: core: Add msm8939 DT compatible and resrouce struct

The msm8936/msm8939 venus contains two cores which allow for simultaneous
encoding or decoding.

An evolution of the msm8916 IP block, some higher clock rates, bandwidth
and H265 is supported.

Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>