BUG/MINOR: mworker: doesn't launch the program postparser

When in wait mode, the mworker-prog postparser is launched, but
unfortunately the child structure doesn't contain all required
information to be able to launch the test.

This test is only required when doing a configuration parsing.

Must be backported as far as 2.0.

(cherry picked from commit 5f47b2e28050066254397873401d3f087ecef1c1)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
diff --git a/src/mworker-prog.c b/src/mworker-prog.c
index abaf46b..f062489 100644
--- a/src/mworker-prog.c
+++ b/src/mworker-prog.c
@@ -328,6 +328,11 @@
 	int err_code = 0;
 	struct mworker_proc *child;
 
+	/* we only need to check this during configuration parsing,
+	 * wait mode doesn't have the complete description of a program */
+	if (global.mode & MODE_MWORKER_WAIT)
+		return err_code;
+
 	list_for_each_entry(child, &proc_list, list) {
 		if (child->reloads == 0 && (child->options & PROC_O_TYPE_PROG)) {
 			if (child->command == NULL) {