net/mlx5: DR, Add check for flex parser ID value

Allow only legal values for flex parser ID - values from 0 to 7.
For other values skip the parser, and as a result the matcher creation
will fail for using invalid flex parser ID.

Signed-off-by: Hamdan Igbaria <hamdani@nvidia.com>
Signed-off-by: Yevgeny Kliteynik <kliteyn@nvidia.com>