net/mlx5: EQ, Create all EQs in one place

Instead of creating the EQ table in three steps at driver load,
 - allocate irq vectors
 - allocate async EQs
 - allocate completion EQs
Gather all of the procedures into one function in eq.c and call it from
driver load.

This will help us reduce the EQ and EQ table private structures
visibility to eq.c in downstream refactoring.

Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>