fix error "E254: Cannot allocate color none"

[jefersonbelmiro]

--- src/syntax.c.orig   2016-06-16 11:43:49.310477225 +0200
+++ src/syntax.c        2016-06-16 11:43:49.310477225 +0200
@@ -8475,7 +8475,7 @@
     static guicolor_T
 color_name2handle(char_u *name)
 {
-    if (STRCMP(name, "NONE") == 0)
+    if (STRICMP(name, "NONE") == 0)
        return INVALCOLOR;
 
     if (STRICMP(name, "fg") == 0 || STRICMP(name, "foreground") == 0)