net/mlx4_core: Fix wrong reading of reserved_eqs

We mistakenly read the reserved_eqs field as a standard
numeric value rather than a log2 value.

Signed-off-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>