FortranCInterface: Compile separate Fortran lib in VerifyC[XX]

The Intel Fortran plugin for Visual Studio requires Fortran source files
to be compiled in a separate target from C and C++ code.  Compile the
VerifyFortran.f source file in a separate library and link the main
VerifyFortanC executable to it.

Modules/FortranCInterface/Verify/CMakeLists.txt

@@ -24,7 +24,9 @@ include(FortranCInterface)
 FortranCInterface_HEADER(VerifyFortran.h SYMBOLS VerifyFortran)
 include_directories(${VerifyFortranC_BINARY_DIR})
 
-add_executable(VerifyFortranC main.c VerifyC.c VerifyFortran.f ${VerifyCXX})
+add_library(VerifyFortran STATIC VerifyFortran.f)
+add_executable(VerifyFortranC main.c VerifyC.c ${VerifyCXX})
+target_link_libraries(VerifyFortranC VerifyFortran)
 
 if(NOT VERIFY_CXX)
   # The entry point (main) is defined in C; link with the C compiler.