net/mlx5: Enhance diagnostics info for TX/RX reporters

Add ts_format to 'Common Config' section of the TX/RX devlink reporters
diagnostics info. Possible values for ts_format: 'RT' or 'FRC'
which stands for: Real Time and Free Running Counters correspondingly.

Signed-off-by: Aya Levin <ayal@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>