Input: add ROHM BU21013 touch panel controller support

Add the ROHM BU21013 capacitive touch panel controller support with
i2c interface.

Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Naveen Kumar Gaddipati <naveen.gaddipati@stericsson.com>
Acked-by: Henrik Rydberg <rydberg@euromail.se>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>