ENGR00217687 [MX6SL_ARM2/EVK] Fix no perfmon directory

The problem is caused because the board init routine don't add the
corresponding device node. Problem resolved after add them
Signed-off-by: Eric Sun <jian.sun@freescale.com>

arch/arm/mach-mx6/board-mx6sl_arm2.c

@@ -1254,6 +1254,10 @@ static void __init mx6_arm2_init(void)
 	imx6sl_add_dcp();
 	imx6sl_add_rngb();
 
+	imx6q_add_perfmon(0);
+	imx6q_add_perfmon(1);
+	imx6q_add_perfmon(2);
+
 	pm_power_off = mx6_snvs_poweroff;
 }
 

arch/arm/mach-mx6/board-mx6sl_evk.c

@@ -1266,6 +1266,10 @@ static void __init mx6_evk_init(void)
 	imx6sl_add_dcp();
 	imx6sl_add_rngb();
 
+	imx6q_add_perfmon(0);
+	imx6q_add_perfmon(1);
+	imx6q_add_perfmon(2);
+
 	pm_power_off = mx6_snvs_poweroff;
 }