irqchip/mxs: Include linux/irqchip/mxs.h

This header contains the definition for icoll_handle_irq(), which
is used in arch/arm/mach-mxs/mach-mxs.c, without this we get a warning
about a missing prototype when building with W=1.

Signed-off-by: Arnd Bergmann <[email protected]>
Acked-by: Shawn Guo <[email protected]>
Signed-off-by: Marc Zyngier <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

Author: arndb

drivers/irqchip/irq-mxs.c

@@ -9,6 +9,7 @@
 #include <linux/init.h>
 #include <linux/irq.h>
 #include <linux/irqchip.h>
+#include <linux/irqchip/mxs.h>
 #include <linux/irqdomain.h>
 #include <linux/io.h>
 #include <linux/of.h>