dt-bindings: iio: bma255: Allow multiple interrupts

BMA253 has two interrupt pins (INT1 and INT2) that can be configured
independently. At the moment the bmc150-accel driver does not make use
of them but it might be able to in the future, so it's useful to already
specify all available interrupts in the device tree.

Set maxItems: 2 for interrupts to allow specifying a second one.
This is necessary as preparation to move the bosch,bma254 compatible
from bosch,bma180.yaml to bosch,bma255.yaml since bma180 allows two
interrupts, but BMA254 is better supported by the bmc150-accel driver.
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
Link: https://lore.kernel.org/r/20210611080903.14384-9-stephan@gerhold.netSigned-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

Documentation/devicetree/bindings/iio/accel/bosch,bma255.yaml

@@ -32,7 +32,12 @@ properties:
   vddio-supply: true
 
   interrupts:
-    maxItems: 1
+    minItems: 1
+    maxItems: 2
+    description: |
+      The first interrupt listed must be the one connected to the INT1 pin,
+      the second (optional) interrupt listed must be the one connected to the
+      INT2 pin (if available).
 
   mount-matrix:
     description: an optional 3x3 mounting rotation matrix.