staging: rtl8192e: Remove variables fraglength and packetlength

Remove unused variables fraglength and packetlength as they are set and
never evaluated.

Signed-off-by: Philipp Hortmann <philipp.g.hortmann@gmail.com>
Link: https://lore.kernel.org/r/cca48e6e3d4d32010699118d55fd82b1dbc6eda6.1708461563.git.philipp.g.hortmann@gmail.com


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