[ARM] pxa: fix incorrect initialization of mfp sysdev when not pxa2xx

The initialization of mfp sysdev in pxa2xx_mfp_init() shall really be
avoided when !cpu_is_pxa2xx().
Signed-off-by: NEric Miao <eric.miao@marvell.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

arch/arm/mach-pxa/mfp-pxa2xx.c

@@ -338,6 +338,9 @@ static int __init pxa2xx_mfp_init(void)
 {
 	int i;
 
+	if (!cpu_is_pxa2xx())
+		return 0;
+
 	if (cpu_is_pxa25x())
 		pxa25x_mfp_init();