MAINTAINERS: Add Marvell mvebu clock drivers

drivers/clk/mvebu/ is missing a maintainers entry. Add it to the
existing entry for the Marvell mvebu platforms.

Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230327-mvebu-clk-fixes-v2-1-8333729ee45d@kernel.org


Signed-off-by: Stephen Boyd <sboyd@kernel.org>