default uninit_bridges when not WITH_VALE
linux/configure: check for ethtool set_channels

ETHTOOL_SCHANNELS may be defined even if the
corresponding set_channels operation does not
exist in ethtool_ops (this is the case in
CentOS 6.5). Therefore, we have to do
the existence check by ourselves.
linux: explicitly include nsproxy.h

This fixes a compile error on some versions
of linux.
linux: build net_ns on old kernels
linux: use NETDEV_OPS feature macro

We already had the NETDEV_OPS feature macro, but the patched
code was still relying on the linux version code.
linux/configure: improved driver selection
linux/make: use the same %.o build rule as Kbuild

Our linux Kbuild file includes the rules for %.o building,
since most netmap files are not in the LINUX directory, and
Kbuild does not support VPATH.

Before this patch, the recipe we were using was not the same
as the corresponding one in linux/scripts/Makefile.build.
This was causing annoying WARNINGs and, possibily, incomplete
rebuilds after file changes.
linux/configure: find out alloc_netdev args number

Another arg was added in 3.17.
linux/scripts: remove stale use of 'make drivers'
linux/configure: check for IXGBE_TX_DESC version
linux/ixgbe: backport to version 2.6.35
linux/ixgbe: adapt to old driver versions

The ixgbe driver moved from [rt]x_ring arrays
of struct ixgbe_ring's to arrays of pointers
in 2.6.34.
linux/ixgbe: backport to 2.6.32

*** untested ***
linux/configure: always use our own split_page

split_page() is always defined, but it may be exported
or not. Detecting the export is very hard to do in a
reliable way, therefore we always use our own.
drop x86-specific examples from default build

testlock and testcsum use x86-specific asm statements
and cannot be compiled on other architectures such as ARM or
mips.
linux/configure: build apps in separate dir