Input: synaptics-rmi4 - make array rmi_f54_report_type_names static

The array rmi_f54_report_type_names is local to the source and does
not need to be in global scope, so make it static. Also make the array
const char * const.

Cleans up sparse warning:
symbol 'rmi_f54_report_type_names' was not declared. Should it be static?
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/rmi4/rmi_f54.c

@@ -73,7 +73,7 @@ enum rmi_f54_report_type {
 	F54_MAX_REPORT_TYPE,
 };
 
-const char *rmi_f54_report_type_names[] = {
+static const char * const rmi_f54_report_type_names[] = {
 	[F54_REPORT_NONE]		= "Unknown",
 	[F54_8BIT_IMAGE]		= "Normalized 8-Bit Image",
 	[F54_16BIT_IMAGE]		= "Normalized 16-Bit Image",