[glib] Fix missing zlib.h in subprojects/zlib/ with Visual Studio

[Philip Withnall <pwithnall src gnome org>]

commit a79ca79a85a717f6eb50a3b1753c7e8080a31881
Author: Kouhei Sutou <kou clear-code com>
Date:   Sat Oct 14 00:57:52 2017 +0900

    Fix missing zlib.h in subprojects/zlib/ with Visual Studio
    
    https://bugzilla.gnome.org/show_bug.cgi?id=788975

 meson.build |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/meson.build b/meson.build
index efb4be3..208c230 100644
--- a/meson.build
+++ b/meson.build
@@ -1464,7 +1464,7 @@ else
       if libz_dep.found()
         zlib_libname = '-lzlib'
       else
-        zlib_dep = subproject('zlib').get_variable('zlib_dep')
+        libz_dep = subproject('zlib').get_variable('zlib_dep')
       endif
     endif
   endif