autotest/virt-test — pull request #1263 by spcui (2013-12-18 09:16:07+00:00)
Title: qemu.tests.cfg: add remove_image_stg for usb_storage

need to remove the origin image and create a new image for format_disk
when running every usb_storage subcase.

Signed-off-by: Shuping Cui