init/main.c: remove prototype for softirq_init()

It's already available in <linux/interrupt.h>
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

init/main.c

@@ -124,7 +124,6 @@ EXPORT_SYMBOL(system_state);
 extern void time_init(void);
 /* Default late time init is NULL. archs can override this later. */
 void (*__initdata late_time_init)(void);
-extern void softirq_init(void);
 
 /* Untouched command line saved by arch-specific code. */
 char __initdata boot_command_line[COMMAND_LINE_SIZE];