clk: efm32gg: Remove clk.h include
Clock provider drivers generally shouldn't include clk.h because
it's the consumer API. Remove the include here because this is a
provider driver.
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>