curl: add --fail-with-body

Prevent both --fail and --fail-with-body on the same command line.

Verify with test 349, 360 and 361.

Closes #6449

src/tool_help.c

@@ -268,6 +268,9 @@ static const struct helptxt helptext[] = {
   {"    --fail-early",
    "Fail on first transfer error, do not continue",
    CURLHELP_CURL},
+  {"    --fail-with-body",
+   "Fail on HTTP errors but save the body",
+   CURLHELP_HTTP | CURLHELP_OUTPUT},
   {"    --false-start",
    "Enable TLS False Start",
    CURLHELP_TLS},