FindLAPACK: Additional libraries for MKL+gfortran combination

As per Intel MKL command line advisor, "libdl" is added to the list of
libraries that provide LAPACK functionality. Furthermore, the implicit
link directories are added to the searched libraries to allow finding
of "libgomp".

Modules/FindLAPACK.cmake

@@ -96,6 +96,9 @@ if (NOT _libdir)
     set(_libdir ENV LD_LIBRARY_PATH)
   endif ()
 endif ()
+
+list(APPEND _libdir "${CMAKE_C_IMPLICIT_LINK_DIRECTORIES}")
+
 foreach(_library ${_list})
   set(_combined_name ${_combined_name}_${_library})
 
@@ -179,6 +182,7 @@ if(BLAS_FOUND)
 if (BLA_VENDOR MATCHES "Intel" OR BLA_VENDOR STREQUAL "All")
   if (NOT WIN32)
     set(LAPACK_mkl_LM "-lm")
+    set(LAPACK_mkl_LDL "-ldl")
   endif ()
   if (CMAKE_C_COMPILER_LOADED OR CMAKE_CXX_COMPILER_LOADED)
     if(LAPACK_FIND_QUIETLY OR NOT LAPACK_FIND_REQUIRED)
@@ -240,7 +244,7 @@ if (BLA_VENDOR MATCHES "Intel" OR BLA_VENDOR STREQUAL "All")
           ""
           "${IT}"
           "${_BLAS_LIBRARIES}"
-          "${CMAKE_THREAD_LIBS_INIT};${LAPACK_mkl_LM}"
+          "${CMAKE_THREAD_LIBS_INIT};${LAPACK_mkl_LM};${LAPACK_mkl_LDL}"
           )
       endif ()
     endforeach ()
@@ -248,6 +252,7 @@ if (BLA_VENDOR MATCHES "Intel" OR BLA_VENDOR STREQUAL "All")
     unset(LAPACK_mkl_ILP_MODE)
     unset(LAPACK_mkl_SEARCH_SYMBOL)
     unset(LAPACK_mkl_LM)
+    unset(LAPACK_mkl_LDL)
   endif ()
 endif()