icd:Expand mock icd memory type bit support

icd:Expand mock icd memory type bit support

Image/buffer memory requirement memoryTypeBits are still just hard-
coded in mock icd, but expand to support more bits for more simulated
memory types. This helps the mock work in conjunction with the devsim
layer so that if a simulated device has more than 5 memory types, the
mock icd won't cause an error.