ARM: imx: remove i.MX6SLL support in i.MX6SL cpu idle driver

i.MX6SLL supports ARM power off in cpu idle, better to reuse
i.MX6SX cpu idle driver instead of i.MX6SL which does NOT
support ARM power off.
Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm/mach-imx/cpuidle-imx6sl.c

@@ -12,7 +12,6 @@
 
 #include "common.h"
 #include "cpuidle.h"
-#include "hardware.h"
 
 static int imx6sl_enter_wait(struct cpuidle_device *dev,
 			    struct cpuidle_driver *drv, int index)
@@ -22,11 +21,9 @@ static int imx6sl_enter_wait(struct cpuidle_device *dev,
 	 * Software workaround for ERR005311, see function
 	 * description for details.
 	 */
-	if (cpu_is_imx6sl())
-		imx6sl_set_wait_clk(true);
+	imx6sl_set_wait_clk(true);
 	cpu_do_idle();
-	if (cpu_is_imx6sl())
-		imx6sl_set_wait_clk(false);
+	imx6sl_set_wait_clk(false);
 	imx6_set_lpm(WAIT_CLOCKED);
 
 	return index;