enter unreal mode

defines.s

@@ -45,6 +45,8 @@
 %define MEMMAP_ENT_FIELD_EXT  0x14
 %define MEMMAP_ENT_FIELD_END  0x18
 
+%define GDT_DESCRIPTOR_SIZE 0x08
+
 ; boot0 base stack frame variable offsets / globals
 ; (we use the same offsets once we copy the variables to the globals section)
 ; -------------------------------------------------------------------------------------------------