arm: mach-k3: am62px: Fix MCU_CLKOUT0 parent clock mux

arm: mach-k3: am62px: Fix MCU_CLKOUT0 parent clock mux

CU_CLKOUT0 can be driven by two input clocks: a 25 MHz and a 50 MHz source.
Currently, the 25 MHz option is not selectable due to an incorrect mux
configuration where the 50 MHz clock is duplicated in the parent list.

This patch fixes the mux setup, allowing proper selection of the 25 MHz
clock source for MCU_CLKOUT0.

Similar configuration is already correctly implemented in AM62 clock
data for 'hsdiv4_16fft_main_2_hsdivout1_clk10', where MCU_CLKOUT0
parent switching behaves as expected.

Link: http://downloads.ti.com/tisci/esd/latest/5_soc_doc/am62px/clocks.html#clocks-for-board0-device
Signed-off-by: Parth Pancholi <parth.pancholi@toradex.com>
Reviewed-by: Bryan Brattlof <bb@ti.com>