Input: edt-ft5x06 - fix build error when compiling wthout CONFIG_DEBUG_FS

This fixes the following breakage:

edt-ft5x06.c: In function edt_ft5x06_ts_remove:
edt-ft5x06.c:846:14: error: struct edt_ft5x06_ts_data has no member named
raw_buffer

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Simon Budig <simon.budig@kernelconcepts.de>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>