xen-swiotlb: fix printk and panic args

Fix printk() and panic() args [swap them] to fix build warnings:

drivers/xen/swiotlb-xen.c:201: warning: format '%s' expects type 'char *', but argument 2 has type 'int'
drivers/xen/swiotlb-xen.c:201: warning: format '%d' expects type 'int', but argument 3 has type 'char *'
drivers/xen/swiotlb-xen.c:202: warning: format '%s' expects type 'char *', but argument 2 has type 'int'
drivers/xen/swiotlb-xen.c:202: warning: format '%d' expects type 'int', but argument 3 has type 'char *'

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

drivers/xen/swiotlb-xen.c

@@ -197,8 +197,8 @@ error:
 		      (xen_io_tlb_nslabs << IO_TLB_SHIFT) >> 20);
 		goto retry;
 	}
-	xen_raw_printk("%s (rc:%d)", rc, m);
-	panic("%s (rc:%d)", rc, m);
+	xen_raw_printk("%s (rc:%d)", m, rc);
+	panic("%s (rc:%d)", m, rc);
 }
 
 void *