compat-wireless: backport sk_add_backlog() calls through a patch

compat-wireless: backport sk_add_backlog() calls through a patch

v2.6.34-rc2~48 got 8eae939f net: add limit for socket backlog
This adds sk_add_backlog_limitted() which makes the backlog
have a size, and therefore adding an skb to the backlog can
fail, a later patch changed all non-limitted calls to use the
limitted caller via a3a858ff. The older kernels don't have a
size and as such always are successfull when adding to the
backlog.

An overload is possible but complex in C so just backport this
via a patch. This fixes this compile issue with compat-wireless
when on kernels older than 2.6.34:

 CC [M]  /home/philipp/kernel/build_i586/compat-wireless-2010-07-12/net/bluetooth/l2cap.o
/home/philipp/kernel/build_i586/compat-wireless-2010-07-12/net/bluetooth/l2cap.c: In function 'l2cap_data_channel':
/home/philipp/kernel/build_i586/compat-wireless-2010-07-12/net/bluetooth/l2cap.c:4352: error: void value not ignored as it ought to be
make[4]: *** [/home/philipp/kernel/build_i586/compat-wireless-2010-07-12/net/bluetooth/l2cap.o] Error 1
make[3]: *** [/home/philipp/kernel/build_i586/compat-wireless-2010-07-12/net/bluetooth] Error 2
make[2]: *** [_module_/home/philipp/kernel/build_i586/compat-wireless-2010-07-12] Error 2
make[2]: Leaving directory `/home/philipp/kernel/build_i586/linux-2.6.27.48-astlinux'
make[1]: *** [modules] Error 2
make[1]: Leaving directory `/home/philipp/kernel/build_i586/compat-wireless-2010-07-12'
make: *** [/home/philipp/kernel/build_i586/compat-wireless-2010-07-12/net/wireless/lib80211.ko] Error 2

Reported-by: "Philip A. Prindeville" <philipp_subx@redfish-solutions.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>