net/mlx5: Check for SQ and not RQ state when modifying hairpin SQ
When modifying hairpin SQ, instead of checking if the next state equals
to MLX5_SQC_STATE_RDY, we compare it against the MLX5_RQC_STATE_RDY enum
value.
The code worked since both of MLX5_RQC_STATE_RDY and MLX5_SQC_STATE_RDY
have the same value today.