FortranCInterface: Work around mingw32-make trouble with parens

The mingw32-make tool does not handle parenthesis in the path to a
source file consistently.  When CMake is installed in a typical location
like "c:\Program Files (x86)\CMake 2.8\" the mingw32-make tool fails on
the FortranCInterface detection project sometimes with errors like

 >mingw32-make -f CMakeFiles\myfort.dir\build.make CMakeFiles/myfort.dir/my_module.f90.obj
 mingw32-make: *** No rule to make target `x86)/CMake 2.8/share/cmake-2.8/Modules/FortranCInterface/my_module.f90)',
 needed by `CMakeFiles/myfort.dir/my_module.f90.obj'.  Stop.

due to parens in the path to the FortranCInterface source directory.
However, the behavior varies with the file name of build.make:

 >copy CMakeFiles\myfort.dir\build.make CMakeFiles\myfort.dir\build2.make
 >mingw32-make -f CMakeFiles\myfort.dir\build2.make CMakeFiles/myfort.dir/my_module.f90.obj
 [  3%] Building Fortran object CMakeFiles/myfort.dir/my_module.f90.obj

Tested with

 >mingw32-make -v
 GNU Make 3.82
 Built for i386-pc-mingw32

Work around the problem by copying the whole FortranCInterface source
directory in to the project build tree.

Modules/FortranCInterface.cmake

@@ -116,6 +116,14 @@ endforeach()
 #-----------------------------------------------------------------------------
 set(FortranCInterface_SOURCE_DIR ${CMAKE_ROOT}/Modules/FortranCInterface)
 
+# MinGW's make tool does not always like () in the path
+if("${CMAKE_GENERATOR}" MATCHES "MinGW" AND
+    "${FortranCInterface_SOURCE_DIR}" MATCHES "[()]")
+  file(COPY ${FortranCInterface_SOURCE_DIR}/
+    DESTINATION ${CMAKE_BINARY_DIR}/CMakeFiles/FortranCInterfaceMinGW)
+  set(FortranCInterface_SOURCE_DIR ${CMAKE_BINARY_DIR}/CMakeFiles/FortranCInterfaceMinGW)
+endif()
+
 # Create the interface detection project if it does not exist.
 if(NOT FortranCInterface_BINARY_DIR)
   set(FortranCInterface_BINARY_DIR ${CMAKE_BINARY_DIR}/CMakeFiles/FortranCInterface)