IRQL levels

#define PASSIVE_LEVEL 0x0
#define APC_LEVEL 0x1
#define DISPATCH_LEVEL 0x2
#define IPI_LEVEL 0xe
#define POWER_LEVEL 0xf
#define PROFILE_LEVEL 0xf
#define HIGH_LEVEL 0xf
#ifdef NT_UP
#define SYNCH_LEVEL 0x2
#else
#define SYNCH_LEVEL 0xc
#endif