clk: moxart: Include clk.h

This clock provider uses the consumer API, so include clk.h
explicitly.

Cc: Jonas Jensen <jonas.jensen@gmail.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

drivers/clk/clk-moxart.c

@@ -10,6 +10,7 @@
  * warranty of any kind, whether express or implied.
  */
 
+#include <linux/clk.h>
 #include <linux/clk-provider.h>
 #include <linux/io.h>
 #include <linux/of_address.h>