clk: mvebu: Remove corediv clock from Armada XP

There is no corediv clock on Armada XP, so this is unnecessary.

Signed-off-by: Kevin Smith <kevin.smith@elecsyscorp.com>
Acked-by: Michael Turquette <mturquette@baylibre.com>
Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>