MAINTAINERS: add include/dt-bindings/clock to COMMON CLK FRAMEWORK

Maintainers of the directory Documentation/devicetree/bindings/clock
are also the maintainers of the corresponding directory in
include/dt-bindings/clock.

Add the file entry for include/dt-bindings/clock to the appropriate
section in MAINTAINERS.

Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Link: https://lore.kernel.org/r/20220613085100.402-1-lukas.bulwahn@gmail.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>