[SCSI] ipr: add writeq definition if needed

Compiling the driver will fail on 32 bit powerpc and other
architectures where writeq is not defined.  This patch adds a
definition for writeq.
Signed-off-by: Wayne Boyer <wayneb@linux.vnet.ibm.com>
Acked-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

drivers/scsi/ipr.h

@@ -1860,4 +1860,12 @@ static inline int ipr_sdt_is_fmt2(u32 sdt_word)
 	return 0;
 }
 
+#ifndef writeq
+static inline void writeq(u64 val, void __iomem *addr)
+{
+        writel(((u32) (val >> 32)), addr);
+        writel(((u32) (val)), (addr + 4));
+}
 #endif
+
+#endif /* _IPR_H */