configs: imx8mp_beacon: Select SPL_CLK_IMX8MP

In preparation to remove manual references for enabling some clocks,
enable SPL_CLK_IMX8MP which automatically enables SPL_CCF and
SPL_CLK_COMPOSITE_CCF which permit various drivers to activate
their respective clocks automatically.

Signed-off-by: Adam Ford <aford173@gmail.com>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
1 file changed