Importing static lib

[stigrj]

Reading MRCPPConfig.cmake fails when MRCPP is build as static lib:

CMake Error at /cluster/home/stig/dev/mrcpp-intel-static/share/cmake/MRCPP/MRCPPConfig.cmake:118 (get_filename_component):
  get_filename_component called with incorrect number of arguments
Call Stack (most recent call first):
  external/upstream/fetch_mrcpp.cmake:1 (find_package)
  cmake/custom/main.cmake:63 (include)
  CMakeLists.txt:62 (include)