In "struct zet6223_ts", the 'vcc' and 'vio' fields are unused.

So, remove them.

Found with cppcheck, unusedStructMember.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/3065d885341e2730dd3e7905d75514796a8c25e4.1715507858.git.christophe.jaillet@wanadoo.frSigned-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>