So that "bitbake <image> -ccleansstate" can remove qemuboot.conf
(From OE-Core rev: 0704f15d1ad7483f80ffa18fa32b6115923641cf)
Signed-off-by: Robert Yang <liezhi.yang@windriver.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>