drm: xlnx: hdmi: Add FRL related data structures

commit  185a9edb4f40584938b9585dae5de63862b0941d from
https://github.com/Xilinx/linux-xlnx.git

 xlnx_rebase_v5.10

This patch adds all the enums, macros and data structures needed to
support FRL mode.

Signed-off-by: Venkateshwar Rao Gannavarapu <venkateshwar.rao.gannavarapu@xilinx.com>
State: pending
Signed-off-by: Quanyang Wang <quanyang.wang@windriver.com>