[PATCH] ppc32 8xx: Added setbitsXX/clrbitsXX macro for read-modify-write operations

This adds setbitsXX/clrbitsXX macro for read-modify-write operations
and converts the 8xx core and drivers to use them.

Signed-off-by: Vitaly Bordug <vbordug@ru.mvista.com>
Signed-off-by: Marcelo Tosatti <marcelo.tosatti@cyclades.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/arch/ppc/syslib/m8xx_wdt.c b/arch/ppc/syslib/m8xx_wdt.c
index df6c955..ac11d7b 100644
--- a/arch/ppc/syslib/m8xx_wdt.c
+++ b/arch/ppc/syslib/m8xx_wdt.c
@@ -41,8 +41,7 @@
 
 	m8xx_wdt_reset();
 
-	out_be16(&imap->im_sit.sit_piscr, in_be16(&imap->im_sit.sit_piscr) | PISCR_PS);	/* clear irq */
-
+	setbits16(&imap->im_sit.sit_piscr, PISCR_PS);
 	return IRQ_HANDLED;
 }