[Unittests] Fix RISCV unit tests build

/usr/bin/ld: CMakeFiles/RISCVTests.dir/RISCVInstrInfoTest.cpp.o: undefined
reference to symbol '_ZNK4llvm12LocationSize5printERNS_11raw_ostreamE'
/usr/bin/ld: /work/kparzysz/git/llvm.org/b/x86/lib/libLLVMAnalysis.so.19.0
git: error adding symbols: DSO missing from command line
collect2: error: ld returned 1 exit status

The undefined symbol is
llvm::LocationSize::print(llvm::raw_ostream&) const