sensor: sensor_axis_align: clarify defgroup

Rename and clarify the @defgroup SENSOR_AXIS_ALIGN to better reflect its
purpose. Replace the vague "DT Options" title with a more descriptive
name: "Sensor axis alignment DT options".

This improves documentation clarity for developers configuring sensor
orientation via Device Tree.

Signed-off-by: Gaetan Perrot <gaetan.perrot@spacecubics.com>

include/zephyr/dt-bindings/sensor/sensor_axis_align.h

@@ -6,7 +6,7 @@
 #define ZEPHYR_INCLUDE_DT_BINDINGS_SENSOR_AXIS_ALIGN_H_
 
 /**
- * @defgroup SENSOR_AXIS_ALIGN DT Options
+ * @defgroup SENSOR_AXIS_ALIGN Sensor axis alignment DT Options
  * @ingroup sensor_interface
  * @{
  */