Input: mxs-lradc - make symbol mxs_lradc_ts_irq_names static

Fixes the following sparse warning:

drivers/input/touchscreen/mxs-lradc-ts.c:33:12: warning:
 symbol 'mxs_lradc_ts_irq_names' was not declared. Should it be static?

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
[dtor: changed to static const char * const]
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/touchscreen/mxs-lradc-ts.c

@@ -30,7 +30,7 @@
 #include <linux/of_irq.h>
 #include <linux/platform_device.h>
 
-const char *mxs_lradc_ts_irq_names[] = {
+static const char * const mxs_lradc_ts_irq_names[] = {
 	"mxs-lradc-touchscreen",
 	"mxs-lradc-channel6",
 	"mxs-lradc-channel7",