feat(nxp-clk): add get_rate for clock muxes

From the get rate callback perspective, all types of clock muxes should
return the frequency of the selected source, regardless of whether it is
an MC_CGM or PLL mux.

Change-Id: I24ae821013b0844e4d62793fde12b53b043a9776
Signed-off-by: Ghennadi Procopciuc <ghennadi.procopciuc@nxp.com>
1 file changed