simplefb: Include clk.h

This driver uses the consumer API, so include clk.h explicitly
instead of impliclty through the provider API.

Cc: Luc Verhaegen <libv@skynet.be>
Cc: Hans de Goede <hdegoede@redhat.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: David Herrmann <dh.herrmann@gmail.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

drivers/video/fbdev/simplefb.c

@@ -26,6 +26,7 @@
 #include <linux/module.h>
 #include <linux/platform_data/simplefb.h>
 #include <linux/platform_device.h>
+#include <linux/clk.h>
 #include <linux/clk-provider.h>
 #include <linux/of_platform.h>