dt-bindings: clock: adi,axi-clkgen: convert old binding to yaml format

[ Upstream commit bd91abb218e0ac4a7402d6c25d383e2a706bb511 ]

This change converts the old binding for the AXI clkgen driver to a yaml
format.

As maintainers, added:
 - Lars-Peter Clausen <lars@metafoo.de> - as original author of driver &
   binding
 - Michael Hennerich <michael.hennerich@analog.com> - as supporter of
   Analog Devices drivers

Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20201013143421.84188-1-alexandru.ardelean@analog.com


Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Stable-dep-of: 47f3f5a82a31 ("dt-bindings: clock: axi-clkgen: include AXI clk")
Signed-off-by: Sasha Levin <sashal@kernel.org>