TT#68300 Fix programs --help output, do not print missing help parameter

The GetOptions() function will pass «$opt_name, $opt_value» to the
function refs in the options spec, which means that the usage()
function will consider that a missing parameters message and print
"help" as being a missing required parameter.

Use an anonymous function to wrap the usage() call and avoid the
unexpected arguments.

Change-Id: I5c10b241da23ccb7aa25a13dd5ebc1b4188b7370

bin/ngcp-api-ping

@@ -14,7 +14,7 @@ my $opts = {
 };
 
 GetOptions( $opts,
-    "help|h" => \&usage,
+    "help|h" => sub { usage() },
     "verbose",
 ) or usage();
 

bin/ngcp-create-customer

@@ -16,7 +16,7 @@ my $opts = {
 };
 
 GetOptions( $opts,
-    "help|h" => \&usage,
+    "help|h" => sub { usage() },
     "billing_profile_id=i",
     "contact_id=i",
     "type=s",

bin/ngcp-create-domain

@@ -17,7 +17,7 @@ my $opts = {
 };
 
 GetOptions( $opts,
-    "help|h" => \&usage,
+    "help|h" => sub { usage() },
     "domain=s",
     "reseller_id=i",
     "skip_xmpp",

bin/ngcp-create-subscriber

@@ -15,7 +15,7 @@ my $opts = {
 };
 
 GetOptions( $opts,
-    "help|h" => \&usage,
+    "help|h" => sub { usage() },
     "customer_id=i",
     "username|u=s",
     "password|p=s",

bin/ngcp-credit-warning

@@ -25,7 +25,7 @@ my $opts = {
 my $config;
 
 GetOptions( $opts,
-    "help|h" => \&usage,
+    "help|h" => sub { usage() },
     "verbose",
 ) or usage();
 

bin/ngcp-delete-domain

@@ -17,7 +17,7 @@ my $opts = {
 };
 
 GetOptions( $opts,
-    "help|h" => \&usage,
+    "help|h" => sub { usage() },
     "domain=s",
     "skip_xmpp",
     "skip_sip",

bin/ngcp-fraud-notifier

@@ -38,7 +38,7 @@ my $opts = {
 my $config;
 
 GetOptions( $opts,
-    "help|h" => \&usage,
+    "help|h" => sub { usage() },
     "verbose",
 ) or usage();
 

bin/ngcp-get-customer

@@ -14,7 +14,7 @@ my $opts = {
 };
 
 GetOptions( $opts,
-    "help|h" => \&usage,
+    "help|h" => sub { usage() },
     "customer_id=i",
     "verbose",
 ) or usage();

bin/ngcp-sound-set

@@ -14,7 +14,7 @@ my $opts = {
 };
 
 GetOptions( $opts,
-    "help|h" => \&usage,
+    "help|h" => sub { usage() },
     "id=i",
     "verbose",
 ) or usage();

bin/ngcp-terminate-customer

@@ -14,7 +14,7 @@ my $opts = {
 };
 
 GetOptions( $opts,
-    "help|h" => \&usage,
+    "help|h" => sub { usage() },
     "customer_id=i",
     "verbose",
 ) or usage();

bin/ngcp-terminate-subscriber

@@ -14,7 +14,7 @@ my $opts = {
 };
 
 GetOptions( $opts,
-    "help|h" => \&usage,
+    "help|h" => sub { usage() },
     "username=s",
     "domain=s",
     "verbose",