Explicitly include DesignCompile files
Explicitly include DesignCompile files

Rationale:
- When new file is added, GLOB option would not include it by default.
Now it needs to be explicitly mentioned.
- Unit test files are no longer caught by default - no need to filter
them out and they have their own targets
- Avoid using list(FILTER ... ) command

Signed-off-by: Rafal Kapuscik <6a7be3d4d2afb8bd1d0b737d2f237a3071b5d393@antmicro.com>

chipsalliance/Surelog,alainmarcel/Surelog,chipsalliance/Surelog,alainmarcel/Surelog,alainmarcel/Surelog,alainmarcel/Surelog,chipsalliance/Surelog,chipsalliance/Surelog