phy: ti: j721e-wiz: Model the internal clocks without device tree input

phy: ti: j721e-wiz: Model the internal clocks without device tree input

commit 091876cc355d ("phy: ti: j721e-wiz: Add support for WIZ module
present in TI J721E SoC") modeled the internal clocks depending on the
subnodes that are populated in device tree. However recent discussions
in the mailing list [1] suggested to just add #clock cells in the parent
DT node and model the clocks within the driver.

Model the mux clocks without device tree input for AM64x SoC. Don't
remove the earlier design since DT nodes for J7200 and J721e are already
upstreamed.

[1] -> http://lore.kernel.org/r/20210108025943.GA1790601@robh.at.kernel.org

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Link: https://lore.kernel.org/r/20210310120840.16447-5-kishon@ti.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>