clk: at91: sama7g5: Allow MCK1 to be exported and referenced in DT

MCK1 feeds the External Bus Interface (EBI). EBI's clock rate is used
to translate EBI's timmings to SMC timings, thus we need to handle MCK1
in the EBI driver. Allow MCK1 to be referenced as a PMC_TYPE_CORE clock
from phandle in DT.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Link: https://lore.kernel.org/r/20220111125310.902856-1-tudor.ambarus@microchip.com


Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>