Input: goodix - fix misspelling of 'ctx'

Fixes the following W=1 kernel build warning(s):

 drivers/input/touchscreen/goodix.c:1168: warning: Function parameter or member 'ctx' not described in 'goodix_config_cb'
 drivers/input/touchscreen/goodix.c:1168: warning: Excess function parameter 'ts' description in 'goodix_config_cb'

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20201112110204.2083435-14-lee.jones@linaro.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>