clk: imx6ul: Remove the duplicate code

clk: imx6ul: Remove the duplicate code

This patch remve the duplicate code. Due to this code, getting following
logs at boot time:

failed to set rate of clk ahb to 99000000: -16
failed to set parent of clk periph to periph_clk2: -16
failed to set parent of clk periph_pre to pll2_bus: -16

Signed-off-by: Vipul Kumar <vipul_kumar@mentor.com>
(cherry picked from commit a0e0c60b7ba99bcd2e308c51326bf92b21a894b8)