CLEANUP: fix typos in comments for contrib/wireshark-dissectors

This fixes a typo in the README of the peers section of this subsystem
and 2 typos in code comments. Groupped together as cleanup to avoid too
many 1 char patches.
diff --git a/contrib/wireshark-dissectors/peers/README b/contrib/wireshark-dissectors/peers/README
index 2021fe1..a81e98c 100644
--- a/contrib/wireshark-dissectors/peers/README
+++ b/contrib/wireshark-dissectors/peers/README
@@ -7,7 +7,7 @@
 
 1) File list
 -------------
- - packet-happp.c: source code for HAProxy Peers Procotol (HAPPP) dissection
+ - packet-happp.c: source code for HAProxy Peers Protocol (HAPPP) dissection
    support.
  - wireshark.happp.dissector.patch: a patch file for wireshark sources to enable HAPPP
    dissection support. Note that this patch file modifies only two files: