qga: Clean up includes

This commit was created with scripts/clean-includes.

All .c should include qemu/osdep.h first.  The script performs three
related cleanups:

* Ensure .c files include qemu/osdep.h first.
* Including it in a .h is redundant, since the .c  already includes
  it.  Drop such inclusions.
* Likewise, including headers qemu/osdep.h includes is redundant.
  Drop these, too.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Konstantin Kostiuk <kkostiuk@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20230202133830.2152150-11-armbru@redhat.com>