[evolution] Include also environment LD_LIBRARY_PATH in gtk-doc-scangobj call

[Milan Crha <mcrha src gnome org>]

commit 17b918c97ab7f9d97d35a11ea7467c7f64093e1d
Author: Milan Crha <mcrha redhat com>
Date:   Mon Nov 12 09:15:42 2018 +0100

    Include also environment LD_LIBRARY_PATH in gtk-doc-scangobj call
    
    Thus it can be used to influence where the needed libraries are
    looked for from the outside.

 cmake/modules/GtkDoc.cmake | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/cmake/modules/GtkDoc.cmake b/cmake/modules/GtkDoc.cmake
index b3519aeb52..1ed45d8c90 100644
--- a/cmake/modules/GtkDoc.cmake
+++ b/cmake/modules/GtkDoc.cmake
@@ -133,7 +133,7 @@ macro(add_gtkdoc _module _namespace _deprecated_guards _srcdirsvar _depsvar _ign
                endif(TARGET ${opt})
        endforeach(opt)
 
-       set(_scangobj_prefix ${CMAKE_COMMAND} -E env 
LD_LIBRARY_PATH="${_scangobj_ld_lib_dirs}:${LIB_INSTALL_DIR}")
+       set(_scangobj_prefix ${CMAKE_COMMAND} -E env 
LD_LIBRARY_PATH="${_scangobj_ld_lib_dirs}:${LIB_INSTALL_DIR}:$ENV{LD_LIBRARY_PATH}")
 
        if(NOT (_scangobj_cflags STREQUAL ""))
                set(_scangobj_cflags --cflags "${_scangobj_cflags}")