[gtksourceview/gnome-3-20] win32: silence a warning with Visual Studio

[Sébastien Wilmet <swilmet src gnome org>]

commit 24eeb0af631c4a0a50110be36c965fbb9c707f60
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Wed Jun 22 13:26:45 2016 +0200

    win32: silence a warning with Visual Studio
    
    The warning was:
    warning C4090: 'function' : different 'const' qualifiers
    
    But it's normally valid C code, so it's probably a false negative of the
    Visual Studio compiler.

 gtksourceview/gtksourceencoding.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/gtksourceview/gtksourceencoding.c b/gtksourceview/gtksourceencoding.c
index 2df70f5..4821747 100644
--- a/gtksourceview/gtksourceencoding.c
+++ b/gtksourceview/gtksourceencoding.c
@@ -673,7 +673,7 @@ gtk_source_encoding_get_default_candidates (void)
 
        encodings_strv = g_variant_get_strv (encodings_variant, NULL);
        encodings_list = strv_to_list (encodings_strv);
-       g_free (encodings_strv);
+       g_free ((gpointer) encodings_strv);
 
        /* Ensure that UTF-8 and CURRENT are present. */
        encodings_list = g_slist_prepend (encodings_list,