MINOR: checks: simplify tcp expect config parser

Reduce copy of parsing portions that is common to all three types of
expect actions.

This reduces the amount of code, helping maintainability and reducing
future change spread.

Functionality is identical.
diff --git a/src/cfgparse-listen.c b/src/cfgparse-listen.c
index be3ae03..911255b 100644
--- a/src/cfgparse-listen.c
+++ b/src/cfgparse-listen.c
@@ -3213,9 +3213,15 @@
 					break;
 				cur_arg++;
 			}
+
 			/* now ptr_arg points to the beginning of a word past any possible
 			 * exclamation mark, and cur_arg is the argument which holds this word.
 			 */
+
+			tcpcheck = calloc(1, sizeof(*tcpcheck));
+			tcpcheck->action = TCPCHK_ACT_EXPECT;
+			tcpcheck->inverse = inverse;
+
 			if (strcmp(ptr_arg, "binary") == 0) {
 				char *err = NULL;
 
@@ -3226,29 +3232,12 @@
 					goto out;
 				}
 
-				tcpcheck = calloc(1, sizeof(*tcpcheck));
-
-				tcpcheck->action = TCPCHK_ACT_EXPECT;
 				if (parse_binary(args[cur_arg + 1], &tcpcheck->string, &tcpcheck->string_len, &err) == 0) {
 					ha_alert("parsing [%s:%d] : '%s %s %s' expects <BINARY STRING> as argument, but %s\n",
 						 file, linenum, args[0], args[1], args[2], err);
 					err_code |= ERR_ALERT | ERR_FATAL;
 					goto out;
 				}
-				tcpcheck->expect_regex = NULL;
-				tcpcheck->inverse = inverse;
-
-				/* tcpcheck comment */
-				cur_arg += 2;
-				if (strcmp(args[cur_arg], "comment") == 0) {
-					if (!*args[cur_arg + 1]) {
-						ha_alert("parsing [%s:%d] : '%s' expects a comment string.\n",
-							 file, linenum, args[cur_arg + 1]);
-						err_code |= ERR_ALERT | ERR_FATAL;
-						goto out;
-					}
-					tcpcheck->comment = strdup(args[cur_arg + 1]);
-				}
 			}
 			else if (strcmp(ptr_arg, "string") == 0) {
 				if (!*(args[cur_arg + 1])) {
@@ -3258,25 +3247,8 @@
 					goto out;
 				}
 
-				tcpcheck = calloc(1, sizeof(*tcpcheck));
-
-				tcpcheck->action = TCPCHK_ACT_EXPECT;
 				tcpcheck->string_len = strlen(args[cur_arg + 1]);
 				tcpcheck->string = strdup(args[cur_arg + 1]);
-				tcpcheck->expect_regex = NULL;
-				tcpcheck->inverse = inverse;
-
-				/* tcpcheck comment */
-				cur_arg += 2;
-				if (strcmp(args[cur_arg], "comment") == 0) {
-					if (!*args[cur_arg + 1]) {
-						ha_alert("parsing [%s:%d] : '%s' expects a comment string.\n",
-							 file, linenum, args[cur_arg + 1]);
-						err_code |= ERR_ALERT | ERR_FATAL;
-						goto out;
-					}
-					tcpcheck->comment = strdup(args[cur_arg + 1]);
-				}
 			}
 			else if (strcmp(ptr_arg, "rstring") == 0) {
 				if (!*(args[cur_arg + 1])) {
@@ -3286,11 +3258,6 @@
 					goto out;
 				}
 
-				tcpcheck = calloc(1, sizeof(*tcpcheck));
-
-				tcpcheck->action = TCPCHK_ACT_EXPECT;
-				tcpcheck->string_len = 0;
-				tcpcheck->string = NULL;
 				error = NULL;
 				if (!(tcpcheck->expect_regex = regex_comp(args[cur_arg + 1], 1, 1, &error))) {
 					ha_alert("parsing [%s:%d] : '%s %s %s' : regular expression '%s': %s.\n",
@@ -3299,19 +3266,6 @@
 					err_code |= ERR_ALERT | ERR_FATAL;
 					goto out;
 				}
-				tcpcheck->inverse = inverse;
-
-				/* tcpcheck comment */
-				cur_arg += 2;
-				if (strcmp(args[cur_arg], "comment") == 0) {
-					if (!*args[cur_arg + 1]) {
-						ha_alert("parsing [%s:%d] : '%s' expects a comment string.\n",
-							 file, linenum, args[cur_arg + 1]);
-						err_code |= ERR_ALERT | ERR_FATAL;
-						goto out;
-					}
-					tcpcheck->comment = strdup(args[cur_arg + 1]);
-				}
 			}
 			else {
 				ha_alert("parsing [%s:%d] : '%s %s' only supports [!] 'binary', 'string', 'rstring', found '%s'.\n",
@@ -3320,6 +3274,18 @@
 				goto out;
 			}
 
+			/* tcpcheck comment */
+			cur_arg += 2;
+			if (strcmp(args[cur_arg], "comment") == 0) {
+				if (!*args[cur_arg + 1]) {
+					ha_alert("parsing [%s:%d] : '%s' expects a comment string.\n",
+						 file, linenum, args[cur_arg + 1]);
+					err_code |= ERR_ALERT | ERR_FATAL;
+					goto out;
+				}
+				tcpcheck->comment = strdup(args[cur_arg + 1]);
+			}
+
 			/* All tcp-check expect points back to the first inverse expect rule
 			 * in a chain of one or more expect rule, potentially itself.
 			 */