This attribute indicates the number of VCCs supported for each VPI
in the Programmable VCC Space. The VCI values of these VCCs
range from 0 to (numVccsPerNonZeroVpi - 1) for each VPI in this
space. For Apc-based cards, the maximum value is 16384. For
CQC-based cards, the maximum value is 2048).
To override the system default, see the AtmIf ConnMap Ov attribute
numVccsPerNonZeroVpi.