Bug#568339: patch for three compiler warnings

[Alex Perry <alex.perry@pamurray.com>]

This patch resolves the three compiler warnings in the function
xft_setfont at draw.c:5476 that was triggering the segfault in
libfontconfig via libXft.  MGP now runs the presentation on which I
originally also observed the crash.  Could we get those into a debian
patched release please?

$ diff -u mgp-1.13a+upstream20090219/draw.c mgp-1.13a+local/draw.c
--- mgp-1.13a+upstream20090219/draw.c   2009-02-15 03:35:19.000000000 -0800
+++ mgp-1.13a+local/draw.c      2010-02-14 14:42:30.000000000 -0800
@@ -5425,7 +5425,6 @@
        char *p, *p2;
        char style[100];
        char font[100];
-       int stlen;

        bzero(style, sizeof(style));
        bzero(font, sizeof(font));
@@ -5471,12 +5470,12 @@
                    XFT_FAMILY, XftTypeString, font,
                    XFT_ENCODING, XftTypeString, registry,
                    XFT_STYLE, XftTypeString, style,
-                   XFT_PIXEL_SIZE, XftTypeDouble, (float)csize, 0);
+                   XFT_PIXEL_SIZE, XftTypeDouble, (float)csize, (char*)0);
        } else {
                xftfont = XftFontOpen(display, screen,
                    XFT_FAMILY, XftTypeString, font,
                    XFT_ENCODING, XftTypeString, registry,
-                   XFT_PIXEL_SIZE, XftTypeDouble, (float)csize, 0);
+                   XFT_PIXEL_SIZE, XftTypeDouble, (float)csize, (char*)0);
        }
        if (xftfont == 0) {
                free(xfont);