Removed fpnew dependency

Created by: Silabs-ArjanB

Removed github dependency on fpnew

fpnew is still cloned if the FPU test case is run, but fpnew is not required to compile the CV32E40P RTL itself.

The content of rtl/include/cv32e40p_pkg.sv needs to be kept in sync with the content of fpnew/src/fpnew_pkg.sv in case FPU=1 is used.

Signed-off-by: Arjan Bink Arjan.Bink@silabs.com