clk: rzg2l: Ignore disable for core clocks

clk: rzg2l: Ignore disable for core clocks

Following on from commit 9a699a0a0d62 ("clk: rzg2l: Ignore enable for
core clocks"), we also need to ignore attempts to disable core clocks to
avoid the need for conditionals around clk_disable_bulk() calls in
drivers which support both RZ/G2L and other Renesas SoCs.

Signed-off-by: Paul Barker <paul.barker.ct@bp.renesas.com>
Reviewed-by: Marek Vasut <marek.vasut+renesas@mailbox.org>