amd64 pcb.h: use 4 hex digits for pcb flags

Sponsored by:	The FreeBSD Foundation
MFC after:	3 days

sys/amd64/include/pcb.h

@@ -76,14 +76,14 @@ struct pcb {
 	uint16_t	pcb_tr;
 
 	u_int		pcb_flags;
-#define	PCB_FULL_IRET	0x01	/* full iret is required */
-#define	PCB_DBREGS	0x02	/* process using debug registers */
-#define	PCB_KERNFPU	0x04	/* kernel uses fpu */
-#define	PCB_FPUINITDONE	0x08	/* fpu state is initialized */
-#define	PCB_USERFPUINITDONE 0x10 /* fpu user state is initialized */
-#define	PCB_KERNFPU_THR	0x20	/* fpu_kern_thread() */
-#define	PCB_32BIT	0x40	/* process has 32 bit context (segs etc) */
-#define	PCB_FPUNOSAVE	0x80	/* no save area for current FPU ctx */
+#define	PCB_FULL_IRET	0x0001	/* full iret is required */
+#define	PCB_DBREGS	0x0002	/* process using debug registers */
+#define	PCB_KERNFPU	0x0004	/* kernel uses fpu */
+#define	PCB_FPUINITDONE	0x0008	/* fpu state is initialized */
+#define	PCB_USERFPUINITDONE 0x0010 /* fpu user state is initialized */
+#define	PCB_KERNFPU_THR	0x0020	/* fpu_kern_thread() */
+#define	PCB_32BIT	0x0040	/* process has 32 bit context (segs etc) */
+#define	PCB_FPUNOSAVE	0x0080	/* no save area for current FPU ctx */
 
 	uint16_t	pcb_initial_fpucw;