The ili251x touch controller needs 5ms delay between sending I2C device
address and register address, and, writing or reading register data.

According to downstream ili251x example code, this 5ms delay is not
required when reading touch samples out of the controller. Implement
such a special case.
Signed-off-by: NMarek Vasut <marex@denx.de>
Link: https://lore.kernel.org/r/20211108005259.480545-1-marex@denx.deSigned-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>