qemu: Reorder cleanup in qemuStateCleanup()

qemu: Reorder cleanup in qemuStateCleanup()

This function is supposed to clean up virQEMUDriver structure and
free individual members. However, it's doing that in random order
which makes it hard to track which members are being freed and
which are not. Do the free in reverse order than the structure
definition - assuming that the most important members (like
mutex) are declared first and freed last.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>