clk: renesas: rzg2l: Remove unused notifiers

notifiers is not used.

Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
Link: https://lore.kernel.org/r/20220304143241.8523-1-phil.edworthy@renesas.com


Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>