CLEANUP: assorted typo fixes in the code and comments

This is 34th iteration of typo fixes
diff --git a/doc/internals/api/event_hdl.txt b/doc/internals/api/event_hdl.txt
index fdcc973..4414bc4 100644
--- a/doc/internals/api/event_hdl.txt
+++ b/doc/internals/api/event_hdl.txt
@@ -874,7 +874,7 @@
 event family struct, a compilation assert triggered by EVENT_HDL_CB_DATA
 will occur. In addition to this, an extra runtime BUG_ON will make
 sure the condition is met when publishing the event.
-The goal here is to force haproxy to fail explicitely so you know that
+The goal here is to force haproxy to fail explicitly so you know that
 something must be done on your side.
 
 3.1 PUBLISHING AN EVENT