do not assume signed char

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@1121 c046a42c-6fe2-441c-8c8c-71466251a162

i386-dis.c

@@ -1832,7 +1832,7 @@ static bfd_vma start_pc;
  * The function returns the length of this instruction in bytes.
  */
 
-static char intel_syntax;
+static int8_t intel_syntax;
 static char open_char;
 static char close_char;
 static char separator_char;