make the functions name consistent

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
diff --git a/sensor.h b/sensor.h
index 8537149..4be90e6 100644
--- a/sensor.h
+++ b/sensor.h
@@ -13,3 +13,6 @@
  *       - initial API and implementation
  *******************************************************************************/
 
+extern int sensor_dump(void);
+extern int sensor_display(void);
+extern int sensor_init(void);