drivers: comparator: fix wrong @SInCE tag

The Comparator API was introduced in 4.0, not 3.7

Signed-off-by: Benjamin Cabé <benjamin@zephyrproject.org>

Author: kartben

include/zephyr/drivers/comparator.h

@@ -10,7 +10,7 @@
 /**
  * @brief Comparator Interface
  * @defgroup comparator_interface Comparator Interface
- * @since 3.7
+ * @since 4.0
  * @version 0.1.0
  * @ingroup io_interfaces
  * @{