mfd: Fix twl-irq function declaration warnings

Fixes following sparse warnings for twl4030 and twl6030 irq files.

drivers/mfd/twl4030-irq.c:783:5: warning: symbol 'twl4030_init_irq' was not
declared. Should it be static?
drivers/mfd/twl4030-irq.c:863:5: warning: symbol 'twl4030_exit_irq' was not
declared. Should it be static?
drivers/mfd/twl4030-irq.c:873:5: warning: symbol 'twl4030_init_chip_irq' was
not declared. Should it be static?

drivers/mfd/twl6030-irq.c:226:5: warning: symbol 'twl6030_init_irq' was not
declared. Should it be static?
drivers/mfd/twl6030-irq.c:290:5: warning: symbol 'twl6030_exit_irq' was not
declared. Should it be static?

Signed-off-by: G, Manjunath Kondaiah <manjugk@ti.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Tony Lindgren <tony@atomide.com>
Cc: Nishanth Menon <nm@ti.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

drivers/mfd/twl-core.h

@@ -0,0 +1,10 @@
+#ifndef __TWL_CORE_H__
+#define __TWL_CORE_H__
+
+extern int twl6030_init_irq(int irq_num, unsigned irq_base, unsigned irq_end);
+extern int twl6030_exit_irq(void);
+extern int twl4030_init_irq(int irq_num, unsigned irq_base, unsigned irq_end);
+extern int twl4030_exit_irq(void);
+extern int twl4030_init_chip_irq(const char *chip);
+
+#endif /*  __TWL_CORE_H__ */

drivers/mfd/twl4030-irq.c

@@ -35,6 +35,7 @@
 
 #include <linux/i2c/twl.h>
 
+#include "twl-core.h"
 
 /*
  * TWL4030 IRQ handling has two stages in hardware, and thus in software.

drivers/mfd/twl6030-irq.c

@@ -38,6 +38,8 @@
 #include <linux/i2c/twl.h>
 #include <linux/platform_device.h>
 
+#include "twl-core.h"
+
 /*
  * TWL6030 (unlike its predecessors, which had two level interrupt handling)
  * three interrupt registers INT_STS_A, INT_STS_B and INT_STS_C.