hppb: Add missing dma-mapping.h include

This fixes the following build-error:

 CC      drivers/parisc/hppb.o
drivers/parisc/hppb.c: In function ‘hppb_probe’:
drivers/parisc/hppb.c:73: error: implicit declaration of function ‘ccio_request_resource’
Signed-off-by: Frank Lichtenheld <frank@lichtenheld.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/parisc/hppb.c

@@ -16,6 +16,7 @@
 #include <linux/init.h>
 #include <linux/mm.h>
 #include <linux/slab.h>
+#include <linux/dma-mapping.h>
 #include <linux/ioport.h>
 
 #include <asm/io.h>