MEDIUM: checks: Use a shared ruleset to store tcp-check rules

All tcp-check rules are now stored in the globla shared list. The ones created
to parse a specific protocol, for instance redis, are already stored in this
list. Now pure tcp-check rules are also stored in it. The ruleset name is
created using the proxy name and its config file and line. tcp-check rules
declared in a defaults section are also stored this way using "defaults" as
proxy name.

For now, all tcp-check ruleset are stored in a list. But it could be a bit slow
to looks for a specific ruleset with a huge number of backends. So, it could be
a good idea to use a tree instead.
diff --git a/include/types/checks.h b/include/types/checks.h
index 941fd2e..fcf30d3 100644
--- a/include/types/checks.h
+++ b/include/types/checks.h
@@ -307,9 +307,8 @@
 	};
 };
 
-#define TCPCHK_RULES_NONE        0x00000000
-#define TCPCHK_RULES_SHARED      0x00000001 /* Set for shared list of tcp-check rules */
-#define TCPCHK_RULES_DEF         0x00000002 /* Ruleset inherited from the default section */
+#define TCPCHK_RULES_NONE           0x00000000
+#define TCPCHK_RULES_UNUSED_TCP_RS  0x00000001 /* An unused tcp-check ruleset exists */
 
 #define TCPCHK_RULES_PGSQL_CHK   0x00000010
 #define TCPCHK_RULES_REDIS_CHK   0x00000020