Add Ara support

Created by: niwis

Support Ara via a custom, parametrised accelerator interface.

• cv64a6_imafdcv_sv39_config_pkg.sv enables V extension
• Pre-processor constant ARIANE_ACCELERATOR_PORT enables the interface between CVA6 and Ara. This may be merged into X-interface at some point.
• FPU is bumped to a SIMD-compatible version

Backwards compatibility should be preserved. Once this is merged, we will change the reference of Ara upstream CVA6.

Merry Christmas!

Depends on #948, #1101, #1102, #1103, #1104, #1105