message: fix another bug in building emp
diff: @@ -71,20 +71,22 @@ prepare-emp:
  compile-emp-tool:
  @cd $(builddir)/EMP/emp-tool
  - @cmake CMakeLists.txt
  - @make -f Makefile
  + @cmake $(builddir)/EMP/emp-tool/CMakeLists.txt
  + @cd $(builddir)/EMP/emp-tool/ && $(MAKE)
  + @cd $(builddir)/EMP/emp-tool/ && $(MAKE) install
  @touch compile-emp-tool
  compile-emp-ot:
  @cd $(builddir)/EMP/emp-ot
  - @cmake CMakeLists.txt
  - @make -f Makefile
  + @cmake $(builddir)/EMP/emp-ot/CMakeLists.txt
  + @cd $(builddir)/EMP/emp-ot/ && $(MAKE)
  + @cd $(builddir)/EMP/emp-ot/ && $(MAKE) install
  @touch compile-emp-ot
  compile-emp-m2pc:
  @cd $(builddir)/EMP/emp-m2pc
  - @cmake CMakeLists.txt
  - @make -f Makefile
  + @cmake $(builddir)/EMP/emp-m2pc/CMakeLists.txt
  + @cd $(builddir)/EMP/emp-m2pc/ && $(MAKE)
  @touch compile-emp-m2pc
  compile-blake:
  