8261299: Use-after-free on failure path in LinuxPackage.c, getJvmLauncherLibPath

Reviewed-by: stuefe, herrick

Author: shipilev

src/jdk.jpackage/linux/native/applauncher/LinuxPackage.c

@@ -324,6 +324,7 @@ char* getJvmLauncherLibPath(void) {
                                                         &launcherLibPath);
         if (popenStatus) {
             free(launcherLibPath);
+            launcherLibPath = NULL;
             goto cleanup;
         }
     }