USB: serial: remove redundant initializations of 'mos_parport'

USB: serial: remove redundant initializations of 'mos_parport'

The pointer mos_parport is being initialized to pp->private_data and
then the assignment is duplicated after a spin lock.  Remove the
initialization as it occurs before the spin lock and it is a redundant
assignment.

Cleans up clang warnings:
drivers/usb/serial/mos7720.c:521:26: warning: Value stored to
'mos_parport' during its initialization is never read
drivers/usb/serial/mos7720.c:557:26: warning: Value stored to
'mos_parport' during its initialization is never read

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>