xxxat() APIs are only available on POSIX platforms. For future
extension to Windows, let's replace the direct call to xxxat()
APIs with a wrapper.
Signed-off-by: Bin Meng <bin.meng@windriver.com>
Message-Id: <20221219102022.2167736-4-bin.meng@windriver.com>
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>