MIPS: Replace setup_irq() by request_irq()

request_irq() is preferred over setup_irq(). Invocations of setup_irq()
occur after memory allocators are ready.

Per tglx[1], setup_irq() existed in olden days when allocators were not
ready by the time early interrupts were initialized.

Hence replace setup_irq() by request_irq().

remove_irq() has been replaced by free_irq() as well.

There were build error's during previous version, couple of which was
reported by kbuild test robot <lkp@intel.com> of which one was reported
by Thomas Bogendoerfer <tsbogend@alpha.franken.de> as well. There were a
few more issues including build errors, those also have been fixed.

[1] https://lkml.kernel.org/r/alpine.DEB.2.20.1710191609480.1971@nanos

Signed-off-by: afzal mohammed <afzal.mohd.ma@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

arch/mips/include/asm/sni.h

@@ -11,6 +11,8 @@
 #ifndef __ASM_SNI_H
 #define __ASM_SNI_H
 
+#include <linux/irqreturn.h>
+
 extern unsigned int sni_brd_type;
 
 #define SNI_BRD_10		   2
@@ -239,6 +241,6 @@ static inline int sni_eisa_root_init(void)
 
 /* common irq stuff */
 extern void (*sni_hwint)(void);
-extern struct irqaction sni_isa_irq;
+extern irqreturn_t sni_isa_irq_handler(int dummy, void *p);
 
 #endif /* __ASM_SNI_H */