irqchip: Move IRQCHIP_DECLARE macro to include/linux/irqchip.h

At the moment the IRQCHIP_DECLARE macro is only declared locally in
drivers/irqchip/irqchip.h. It prevents from using it directly in arch/*
directories whenever irqchip drivers only exist there, which happens in a few
cases (e.g. arc, arm, microblaze and mips).

This patch makes the macro to be globally defined, i.e. in
include/linux/irqchip.h, and thus usable for arch-specific declarations of
irqchip drivers. In this way, it is very similar to what clocksource does (ie
CLOCKSOURCE_OF_DECLARE is defined in include/linux/clocksource.h).

For now, this patch only moves the declaration of the macro
IRQCHIP_DECLARE to the global header 'include/linux/irqchip.h' and make
'drivers/irqchip/irqchip.h' include 'include/linux/irqchip.h'. Later, other
patches will get rid of 'drivers/irqchip/irqchip.h' and modify all the impacted
irqchip drivers.

Signed-off-by: Joel Porquet <joel@porquet.org>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1435865565-14114-1-git-send-email-joel@porquet.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

drivers/irqchip/irqchip.h

@@ -8,21 +8,4 @@
  * warranty of any kind, whether express or implied.
  */
 
-#ifndef _IRQCHIP_H
-#define _IRQCHIP_H
-
-#include <linux/of.h>
-
-/*
- * This macro must be used by the different irqchip drivers to declare
- * the association between their DT compatible string and their
- * initialization function.
- *
- * @name: name that must be unique accross all IRQCHIP_DECLARE of the
- * same file.
- * @compstr: compatible string of the irqchip driver
- * @fn: initialization function
- */
-#define IRQCHIP_DECLARE(name, compat, fn) OF_DECLARE_2(irqchip, name, compat, fn)
-
-#endif
+#include <linux/irqchip.h>

include/linux/irqchip.h

@@ -11,6 +11,20 @@
 #ifndef _LINUX_IRQCHIP_H
 #define _LINUX_IRQCHIP_H
 
+#include <linux/of.h>
+
+/*
+ * This macro must be used by the different irqchip drivers to declare
+ * the association between their DT compatible string and their
+ * initialization function.
+ *
+ * @name: name that must be unique accross all IRQCHIP_DECLARE of the
+ * same file.
+ * @compstr: compatible string of the irqchip driver
+ * @fn: initialization function
+ */
+#define IRQCHIP_DECLARE(name, compat, fn) OF_DECLARE_2(irqchip, name, compat, fn)
+
 #ifdef CONFIG_IRQCHIP
 void irqchip_init(void);
 #else