[RISCV] Sync RISCVFeatures.td implies list with RISCVISAInfo.cpp.

This makes Zcf imply F and Zcd imply D in RISCVFeatures.td. They
were already implied in RISCISAInfo.cpp.

Some test RUN lines had to be removed because they were testing
that Zcf without F or Zcd without D would reject some instructions.