dt-bindings: mfd: LMU: Fix lm3632 dt binding example

Fix the lm3632 dt binding examples as the LCM enable GPIOs
are defined as enable GPIOs per the regulator/lm363x-regulator.txt
bindings document.

Signed-off-by: Dan Murphy <dmurphy@ti.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>