qemux86*.conf: changed dependency task for syslinux
Changed dependency task for syslinux from do_build to
do_populate_sysroot as do_build dependency caused conflicts in
populating image recipe sysroot using conflicting recipes. This
makes do_image_wic task to fail with FileExistsError trying to
copy the same file from two conflicting recipes.
This should also speed up image creation a bit as do_populate_sysroot
task is faster than do_build.
[YOCTO #11295]
Signed-off-by: Ed Bartosh <ed.bartosh@linux.intel.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
