USB: mos7840: correct handling of CS5 setting

commit 78692cc3 upstream.

This patch removes an erroneous check of CSIZE, which made it impossible to set
CS5.

Compiles clean, but couldn't test against hardware.

Signed-off-by: Colin Leitner <colin.leitner@gmail.com>
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>