Input: lm8333 - remove driver

The LM8333 keypad driver relies exclusively on legacy platform data,
has no Device Tree or generic device property support, and has no
users in mainline. The BSP board file it was originally written for
was never upstreamed, and the original author Wolfram Sang confirmed
in the mailing list discussion that it will likely never be converted
to Device Tree and agreed to dropping it.

Remove the driver and its platform data header.

Link: https://lore.kernel.org/r/Zr6I9RB5mibU_12N@google.com
Link: https://lore.kernel.org/r/Zr6PnlsdoyLoX261@shikoro
Acked-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Link: https://patch.msgid.link/20261109072950.3474308-3-dmitry.torokhov@gmail.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>