staging: r8188eu: Remove wrapper around vfree

This call is so simple that there is no need, or use, for a wrapper.

Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Link: https://lore.kernel.org/r/20210805183717.23007-3-Larry.Finger@lwfinger.net


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>