selftests/net: use unique netns name for setup_loopback.sh setup_veth.sh

The setup_loopback and setup_veth use their own way to create namespace.
So let's just re-define server_ns/client_ns to unique name.
At the same time update the namespace name in gro.sh and toeplitz.sh.
As I don't have env to run toeplitz.sh. Here is only the gro test result.

# ./gro.sh
running test ipv4 data
Expected {200 }, Total 1 packets
Received {200 }, Total 1 packets.
...
Gro::large test passed.
All Tests Succeeded!

Acked-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: net: Use "grep -E" instead of "egrep"

The latest version of grep claims the egrep is now obsolete so the build
now contains warnings that look like:
egrep: warning: egrep is obsolescent; using grep -E
fix this using "grep -E" instead.

sed -i "s/egrep/grep -E/g" `grep egrep -rwl tools/testing/selftests/net`

Here are the steps to install the latest grep:

wget http://ftp.gnu.org/gnu/grep/grep-3.8.tar.gz
tar xf grep-3.8.tar.gz
cd grep-3.8 && ./configure && make
sudo make install
export PATH=/usr/local/bin:$PATH

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Link: https://lore.kernel.org/r/1669864248-829-1-git-send-email-yangtiezhu@loongson.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

selftests/net: toeplitz test

To verify that this hash implements the Toeplitz hash function.

Additionally, provide a script toeplitz.sh to run the test in loopback mode
on a networking device of choice (see setup_loopback.sh). Since the
script modifies the NIC setup, it will not be run by selftests
automatically.

Tested:
./toeplitz.sh -i eth0 -irq_prefix <eth0_pattern> -t -6
carrier ready
rxq 0: cpu 14
rxq 1: cpu 20
rxq 2: cpu 17
rxq 3: cpu 23
cpu 14: rx_hash 0x69103ebc [saddr fda8::2 daddr fda8::1 sport 58938 dport 8000] OK rxq 0 (cpu 14)
...
cpu 20: rx_hash 0x257118b9 [saddr fda8::2 daddr fda8::1 sport 59258 dport 8000] OK rxq 1 (cpu 20)
count: pass=111 nohash=0 fail=0
Test Succeeded!

Signed-off-by: Coco Li <lixiaoyan@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>