clk: imx: Convert clock-osc-* back to osc_*

clk: imx: Convert clock-osc-* back to osc_*

Convert clock-osc-24m back to osc_24m and clock-osc-32k back to osc_32k.
These are the clock which match clock tables in Linux. This is now
possible because the clock drivers now resolve clock names based on
clock-names DT property in the CCM DT node.

Signed-off-by: Marek Vasut <marex@denx.de>