etc/kamailio.cfg: corrected a typo ("endabled"), GH #3223

(cherry picked from commit b46afeca6c515f5baf1812ca821321117df6478b)
(cherry picked from commit 33e1638b92c073f58b27232e7985a5ffe6994b7f)
(cherry picked from commit 624066ca10f2b6551b396e9fef9605ccea70ea4b)

etc/kamailio.cfg

@@ -24,7 +24,7 @@
 # *** To run in debug mode:
 #     - define WITH_DEBUG
 #     - debug level increased to 3, logs still sent to syslog
-#     - debugger module loaded with cfgtrace endabled
+#     - debugger module loaded with cfgtrace enabled
 #
 # *** To enable mysql:
 #     - define WITH_MYSQL