wrapper.py: avoid nonaffine array size expression

Packed arrays have a size of n*(n+1)/2, which is nonaffine, causing
problems during polyhedral code generation.  Hide the nonaffine
expression by introducing another parameter representing the array
size and set its nonaffine value in the C wrapper.

Change-Id: Iaba4ddd66e7e59958d390412677f94511ff0cb18
Add -I option

Change-Id: Iff4235b033e7837291c1f738a94a0ab1be9c35b0