cris: add missing declaration of kgdb_init() and breakpoint()

Fix:

  arch/cris/arch-v10/kernel/irq.c:239: error: implicit declaration of function 'kgdb_init'
  arch/cris/arch-v10/kernel/irq.c:240: error: implicit declaration of function 'breakpoint'

Declare these two functions.
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/cris/arch-v10/kernel/irq.c

@@ -20,6 +20,9 @@
 #define crisv10_mask_irq(irq_nr) (*R_VECT_MASK_CLR = 1 << (irq_nr));
 #define crisv10_unmask_irq(irq_nr) (*R_VECT_MASK_SET = 1 << (irq_nr));
 
+extern void kgdb_init(void);
+extern void breakpoint(void);
+
 /* don't use set_int_vector, it bypasses the linux interrupt handlers. it is
  * global just so that the kernel gdb can use it.
  */