Fix exit codes in cert_app
diff --git a/programs/x509/cert_app.c b/programs/x509/cert_app.c
index 5f8636b..1ab7cc7 100644
--- a/programs/x509/cert_app.c
+++ b/programs/x509/cert_app.c
@@ -188,6 +188,7 @@
     {
     usage:
         printf( USAGE );
+        ret = 2;
         goto exit;
     }
 
@@ -500,6 +501,9 @@
     fflush( stdout ); getchar();
 #endif
 
+    if( ret < 0 )
+        ret = 1;
+
     return( ret );
 }
 #endif /* POLARSSL_BIGNUM_C && POLARSSL_ENTROPY_C && POLARSSL_SSL_TLS_C &&