dt-bindings: iio: imu: st_lsm6dsx: add support to i2c pullup resistors

Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

Documentation/devicetree/bindings/iio/imu/st_lsm6dsx.txt

@@ -13,6 +13,7 @@ Required properties:
 Optional properties:
 - st,drdy-int-pin: the pin on the package that will be used to signal
   "data ready" (valid values: 1 or 2).
+- st,pullups : enable/disable internal i2c controller pullup resistors.
 - drive-open-drain: the interrupt/data ready line will be configured
   as open drain, which is useful if several sensors share the same
   interrupt line. This is a boolean property.