Fix to different compile warnings.

Fix to multiple int-conversion
Removal of duplicated function definition in dtudcfonted/util.h
Added XtEventHandler prototypes to mtfgui

cde/programs/dtksh/xmcvt.c

@@ -1272,7 +1272,7 @@ static ModifierState modifierTable[] = {
    {"Mod4Mask",    Mod4Mask},
    {"Mod5Mask",    Mod5Mask},
    {"ShiftMask",   ShiftMask},
-   {NULL,          NULL},
+   {NULL,          0},
 };