[Trivial]Remove unused helper check_temp_folder
[Trivial]Remove unused helper check_temp_folder

Helper check_temp_folder is no longer used after
806bdaf94794532132a933c170520629da4ceb0e, this is to remove it.

Change-Id: I2d965a5bae8ab7f023edcac643b989c10a085c15

rahulunair/nova,klmitch/nova,rahulunair/nova,openstack/nova,mahak/nova,openstack/nova,klmitch/nova,mahak/nova,klmitch/nova,openstack/nova,rahulunair/nova,klmitch/nova,mahak/nova