fix warning in rollout_awx plugin

public_html/deployment/plugins/rollout/awx/rollout_awx.php

@@ -176,7 +176,7 @@ class rollout_awx extends rollout_base {
         
         // ----- Checks:
         $sCmdChecks='';
-        if($aConfig['extravars']){
+        if(isset($aConfig['extravars']) && $aConfig['extravars']){
             $aTmp=json_decode($aConfig['extravars'], 1);
             if (!$aTmp || !is_array($aTmp) || !count($aTmp) ){
                 $sCmdChecks.='echo "ERROR: Value in extravars has wrong Syntax - this is no JSON: '.$aConfig['extravars'].'"; exit 1; ';                
@@ -184,14 +184,14 @@ class rollout_awx extends rollout_base {
             $aConfig['extravars']=json_encode($aTmp);
         }
         
-        if(!(int)$aConfig['inventory']){
+        if(!isset($aConfig['inventory']) || !(int)$aConfig['inventory']){
             $sCmdChecks.='echo "ERROR: no inventory was given."; exit 1; ';
         }
         
         // ----- Send variables having values only
         $aBodyvars=array();
         foreach(['inventory'=>'inventory', 'limit'=>'limit', 'job_tags'=>'tags', 'extra_vars'=>'extravars'] as $sParam=>$sVarkey){
-            if ($aConfig[$sVarkey]) {
+            if (isset($aConfig[$sVarkey]) && $aConfig[$sVarkey]) {
                 $aBodyvars[$sParam]=$aConfig[$sVarkey];
             }
         }