clk: versatile: Drop the legacy IM-PD1 clock code

Now that the non-DT IM-PD1 support code has been removed, drop the clock
related code from clk-impd1.c.

Link: https://lore.kernel.org/r/20200428204945.21067-1-robh@kernel.org


Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-clk@vger.kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>