[glib] glib: fix compiler warning for g_unsetenv_utf8() on windows

[Tim-Philipp Müller <tpm src gnome org>]

commit 59c5b939e2bb288765595d069ffddc837a248786
Author: Tim-Philipp Müller <tim centricular com>
Date:   Wed Jan 10 17:24:36 2018 +0000

    glib: fix compiler warning for g_unsetenv_utf8() on windows
    
    "warning: 'void' function returning a value". Neither
    g_unsetenv_utf8() nor g_unsetenv() return anything.

 glib/genviron.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/glib/genviron.c b/glib/genviron.c
index 70cbce9..9c8151c 100644
--- a/glib/genviron.c
+++ b/glib/genviron.c
@@ -665,7 +665,7 @@ g_setenv_utf8 (const gchar *variable,
 void
 g_unsetenv_utf8 (const gchar *variable)
 {
-  return g_unsetenv (variable);
+  g_unsetenv (variable);
 }
 
 #endif