fix(Unprivileged): wait a cycle to update time when nextV =/= v

[Tang-Haojin]

When virt mode changed, time should be updated because we may need a offset version with htimedelta. This commit delays a cycle to update time register because v is actually changed a cycle after nextV =/= v.

[XiangShanRobot]

[Generated by IPC robot]
commit: 2fbb217

commit	astar	copy_and_run	coremark	gcc	gromacs	lbm	linux	mcf	microbench	milc	namd	povray	wrf	xalancbmk
2fbb217	1.814	0.442	2.639	1.231	2.152	2.141	2.361	0.933	1.403	1.985	3.107	2.558	2.267	3.308

master branch:

commit	astar	copy_and_run	coremark	gcc	gromacs	lbm	linux	mcf	microbench	milc	namd	povray	wrf	xalancbmk
718a93f	1.814	0.442	2.639	1.231	2.152	2.141	2.361	0.933	1.407	1.985	3.107	2.558	2.267	3.308
2f0227e	1.814	0.442	2.640	1.231	2.152	2.141	2.361	0.933	1.406	1.985	3.107	2.558	2.267	3.308
ca892e7	1.814	0.442	2.639	1.231	2.152	2.141	2.360	0.933	1.406	1.985	3.107	2.558	2.267	3.308
51aa1b6	1.814	0.442	2.639	1.231	2.152	2.141	2.360	0.933	1.403	1.985	3.107	2.558	2.267	3.308