gpio: pca953x: disable regmap locking for automatic address incrementing

It's a repetition of the commit aa58a21a
  ("gpio: pca953x: disable regmap locking")
which states the following:

  This driver uses its own locking but regmap silently uses
  a mutex for all operations too. Add the option to disable
  locking to the regmap config struct.

Fixes: bcf41dc4 ("gpio: pca953x: fix handling of automatic address incrementing")
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>