[lantiq] ltq-atm: update sock api

[lantiq] ltq-atm: update sock api

update sock api in lantiq atm driver

The ltq-atm driver provides its own replacement for net/atm/common.c:alloc_tx(),
defined in ltq_atm.c:atm_alloc_tx().
The read of sk_wmem_alloc is done in the wrong way, starting with commit
2b85a34e911bf483c27cfdd124aeb1605145dc80 in linux mainline it has to be
done through a specific wrapper.

Signed-off-by: Luca Dariz <luca.dariz@gmail.com>
SVN-Revision: 35991