Remove COMMAND_TAG_NEXTTAG from enum CommandTag.

COMMAND_TAG_NEXTTAG isn't really a valid command tag.  Declaring it
as if it were one prompts complaints from Coverity and perhaps other
static analyzers.  Our only use of it is in an entirely-unnecessary
array sizing declaration, so let's just drop it.

Ranier Vilela

Discussion: https://postgr.es/m/CAEudQAoY0xrKuTAX7W10zsjjUpKBPFRtdCyScb3Z0FB2v6HNmQ@mail.gmail.com

src/backend/tcop/cmdtag.c

@@ -30,7 +30,7 @@ typedef struct CommandTagBehavior
 #define PG_CMDTAG(tag, name, evtrgok, rwrok, rowcnt) \
 	{ name, (uint8) (sizeof(name) - 1), evtrgok, rwrok, rowcnt },
 
-static const CommandTagBehavior tag_behavior[COMMAND_TAG_NEXTTAG] = {
+static const CommandTagBehavior tag_behavior[] = {
 #include "tcop/cmdtaglist.h"
 };
 

src/include/tcop/cmdtag.h

@@ -22,7 +22,6 @@
 typedef enum CommandTag
 {
 #include "tcop/cmdtaglist.h"
-	COMMAND_TAG_NEXTTAG
 } CommandTag;
 
 #undef PG_CMDTAG