MAINTAINERS: update st,vl53l0x.yaml reference

Changeset b4be8bd1 ("dt-bindings:iio:proximity:st,vl53l0x yaml conversion")
renamed: Documentation/devicetree/bindings/iio/proximity/vl53l0x.txt
to: Documentation/devicetree/bindings/iio/proximity/st,vl53l0x.yaml.

Update its cross-reference accordingly.

Fixes: b4be8bd1 ("dt-bindings:iio:proximity:st,vl53l0x yaml conversion")
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

MAINTAINERS

@@ -16958,7 +16958,7 @@ ST VL53L0X ToF RANGER(I2C) IIO DRIVER
 M:	Song Qiang <songqiang1304521@gmail.com>
 L:	linux-iio@vger.kernel.org
 S:	Maintained
-F:	Documentation/devicetree/bindings/iio/proximity/vl53l0x.txt
+F:	Documentation/devicetree/bindings/iio/proximity/st,vl53l0x.yaml
 F:	drivers/iio/proximity/vl53l0x-i2c.c
 
 STABLE BRANCH