rvv-intrinsics API change

[pbb59]

The latest RISCV compiler with vector intrinsics has changed its API to include the vector length (vl) in each primitive. So vfmul(va, vb) is now vfmul(va, vb, vl).

Our programs use an older version of the RISCV compiler, but the commit seems to have been deleted. However, we pulled the repo on NOV 17 2020. The vector programs either need to be updated or an older compiler version must be used.

Note this does not effect programs that don't use RVV. These still work on the newer compiler.