arm64: dts: ti: Add LED controller to phyBOARD-Electra

With commit 9f6ffd0d ("dt-bindings: leds: Convert PCA9532 to dtschema"),
we can now add the LED controller without introducing new dtbs_check warnings.
Add missing I2C LED controller.

Signed-off-by: Wadim Egorov <w.egorov@phytec.de>
Link: https://lore.kernel.org/r/20230505131012.2027309-1-w.egorov@phytec.de


Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>