Use new opt_usage_exit_fail().

opt_usage_and_exit() exits with status 0, and prints to stdout.
This exits status 1 and prints to stderr.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

check-commit-sig.c

@@ -46,7 +46,7 @@ int main(int argc, char *argv[])
  	opt_parse(&argc, argv, opt_log_stderr_exit);
 
 	if (argc != 7)
-		opt_usage_and_exit(NULL);
+		opt_usage_exit_fail("Expected 6 arguments");
 
 	o1 = pkt_from_file(argv[1], PKT__PKT_OPEN)->open;
 	o2 = pkt_from_file(argv[2], PKT__PKT_OPEN)->open;

leak-anchor-sigs.c

@@ -22,7 +22,7 @@ int main(int argc, char *argv[])
  	opt_parse(&argc, argv, opt_log_stderr_exit);
 
 	if (argc != 2)
-		opt_usage_and_exit(NULL);
+		opt_usage_exit_fail("Expected 1 argument");
 
 	s = pkt_from_file(argv[1], PKT__PKT_OPEN_ANCHOR_SCRIPTSIGS)
 		->open_anchor_scriptsigs;

open-anchor-scriptsigs.c

@@ -61,7 +61,7 @@ int main(int argc, char *argv[])
  	opt_parse(&argc, argv, opt_log_stderr_exit);
 
 	if (argc < 3)
-		opt_usage_and_exit(NULL);
+		opt_usage_exit_fail("Expected 2 or more arguments");
 
 	o1 = pkt_from_file(argv[1], PKT__PKT_OPEN)->open;
 	o2 = pkt_from_file(argv[2], PKT__PKT_OPEN)->open;

open-channel.c

@@ -129,7 +129,7 @@ int main(int argc, char *argv[])
  	opt_parse(&argc, argv, opt_log_stderr_exit);
 
 	if (argc < 7)
-		opt_usage_and_exit(NULL);
+		opt_usage_exit_fail("Expected 6 or more arguments");
 
 	if (!hex_decode(argv[1], strlen(argv[1]), &seed, sizeof(seed)))
 		errx(1, "Invalid seed '%s' - need 256 hex bits", argv[1]);

open-commit-sig.c

@@ -44,7 +44,7 @@ int main(int argc, char *argv[])
  	opt_parse(&argc, argv, opt_log_stderr_exit);
 
 	if (argc != 6)
-		opt_usage_and_exit(NULL);
+		opt_usage_exit_fail("Expected 5 arguments");
 
 	o1 = pkt_from_file(argv[1], PKT__PKT_OPEN)->open;
 	o2 = pkt_from_file(argv[2], PKT__PKT_OPEN)->open;