[IA64] fix machine vectors for mmiowb

I left out some of the necessary machine vector magic in the mmiowb patch
which caused the generic build to break.  This patch fixes it up by properly
#defining it and #undefing it and adding a routine to lib/io.c.
Signed-off-by: Jesse Barnes <jbarnes@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

arch/ia64/lib/io.c

@@ -73,6 +73,7 @@ EXPORT_SYMBOL(__ia64_memset_c_io);
 #undef __ia64_writew
 #undef __ia64_writel
 #undef __ia64_writeq
+#undef __ia64_mmiowb
 
 unsigned int
 __ia64_inb (unsigned long port)
@@ -158,4 +159,10 @@ __ia64_readq_relaxed (void __iomem *addr)
 	return ___ia64_readq (addr);
 }
 
+void
+__ia64_mmiowb(void)
+{
+	___ia64_mmiowb();
+}
+
 #endif /* CONFIG_IA64_GENERIC */

include/asm-ia64/io.h

@@ -92,7 +92,7 @@ extern int valid_phys_addr_range (unsigned long addr, size_t *count); /* efi.c *
 #define __ia64_mf_a()	ia64_mfa()
 
 /**
- * __ia64_mmiowb - I/O write barrier
+ * ___ia64_mmiowb - I/O write barrier
  *
  * Ensure ordering of I/O space writes.  This will make sure that writes
  * following the barrier will arrive after all previous writes.  For most
@@ -100,7 +100,7 @@ extern int valid_phys_addr_range (unsigned long addr, size_t *count); /* efi.c *
  *
  * See Documentation/DocBook/deviceiobook.tmpl for more information.
  */
-static inline void __ia64_mmiowb(void)
+static inline void ___ia64_mmiowb(void)
 {
 	ia64_mfa();
 }
@@ -147,6 +147,7 @@ __ia64_mk_io_addr (unsigned long port)
 #define __ia64_writew	___ia64_writew
 #define __ia64_writel	___ia64_writel
 #define __ia64_writeq	___ia64_writeq
+#define __ia64_mmiowb	___ia64_mmiowb
 
 /*
  * For the in/out routines, we need to do "mf.a" _after_ doing the I/O access to ensure