syncqt: Add the missing file stream close calls

Call close explicitly to avoid any issues related to non-closed file
descriptors.

Pick-to: 6.5
Change-Id: I02df30032dc04afd5d135d707eff4a6efe6a3ea5
Reviewed-by: Amir Masoud Abdol <amir.abdol@qt.io>
(cherry picked from commit e9ca247479206b3d6f3815c599a244d9bfbae394)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

src/tools/syncqt/main.cpp

@@ -412,6 +412,7 @@ private:
                     if (!parseArgument(argFromFile))
                         return false;
                 }
+                ifs.close();
                 continue;
             }
 
@@ -1326,6 +1327,7 @@ public:
                 }
             }
         }
+        input.close();
 
         // Error out if namespace checks are failed.
         if (!(skipChecks & NamespaceChecks)) {