selftests: mlxsw: Generalize the parameters of mirror_gre test

Use the number of analyzers taken from the devlink command, instead of
hard-coded value, in order to make the test more generic.

Signed-off-by: Danielle Ratson <danieller@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: mlxsw: Add target for mirror-to-gretap test on spectrum

Add a wrapper around mlxsw/mirror_gre_scale.sh that parameterized number
of offloadable mirrors on Spectrum machines.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>