sgi-gru: add macros for using the UV hub to send interrupts

Add macros for using the UV hub to send interrupts.  Change the IPI code
to use these macros.  These macros will also be used in additional patches
that will follow.

Signed-off-by: Jack Steiner <steiner@sgi.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/ia64/include/asm/uv/uv_hub.h

@@ -305,5 +305,11 @@ static inline int uv_num_possible_blades(void)
 	return 1;
 }
 
+static inline void uv_hub_send_ipi(int pnode, int apicid, int vector)
+{
+	/* not currently needed on ia64 */
+}
+
+
 #endif /* __ASM_IA64_UV_HUB__ */