log UPDATE remove redundant #ifndef (#2119)

Not having the prototype for ly_log_dbg_groups breaks my release builds
(frrouting) due to an implicit function declaration. Judging from the
implementation of ly_log_dbg_groups, it was intended to be present in
release builds and just do nothing. So the removal of the #ifndef
shouldn't be problematic.

Signed-off-by: Thomas Egerer <thomas.egerer@secunet.com>
Co-authored-by: Thomas Egerer <thomas.egerer@secunet.com>
diff --git a/src/log.h b/src/log.h
index 021ab89..c6c1851 100644
--- a/src/log.h
+++ b/src/log.h
@@ -141,8 +141,6 @@
  */
 LIBYANG_API_DECL void ly_temp_log_options(uint32_t *opts);
 
-#ifndef NDEBUG
-
 /**
  * @ingroup log
  * @defgroup dbggroup Debug messages groups
@@ -166,14 +164,13 @@
  * @brief Enable specific debugging messages (independent of log level).
  *
  * To get the current value, the function must be called twice resetting the level by the received value.
+ * Note: does not have any effect on non-debug (Release) builds
  *
  * @param[in] dbg_groups Bitfield of enabled debug message groups (see @ref dbggroup).
  * @return Previous options bitfield.
  */
 LIBYANG_API_DECL uint32_t ly_log_dbg_groups(uint32_t dbg_groups);
 
-#endif
-
 /**
  * @brief Logger callback.
  *