wpu:fix the issue of abnormal power

[Maxpicca-Li]

power comparison：

[XiangShanRobot]

[Generated by IPC robot]
commit: 859dec9

commit	astar	copy_and_run	coremark	gcc	gromacs	lbm	linux	mcf	microbench	milc	namd	povray	wrf	xalancbmk
859dec9	1.854	0.450	2.103	1.190	2.468	2.593	2.329	0.961	1.377	1.427	3.123	2.639	2.451	2.960

master branch:

commit	astar	copy_and_run	coremark	gcc	gromacs	lbm	linux	mcf	microbench	milc	namd	povray	wrf	xalancbmk
363530d
a72b131
05d833a	1.854	0.450	2.103	1.190	2.468	2.593	2.330	0.961	1.377	1.427	3.123	2.639	2.451	2.960
9cb05b4		0.450	2.103				2.330		1.377			2.639
4daa5bf		0.450	2.103	1.190	2.468	2.593	2.329	0.962	1.377	1.427	3.123	2.639		2.960
1e018fb	1.854	0.450	2.103	1.190	2.468	2.593	2.330	0.962	1.377	1.427	3.123	2.639	2.451	2.960
3c71816	1.854	0.450	2.103	1.190	2.468	2.593	2.330	0.962	1.377	1.427	3.123	2.639	2.451	2.960
dfe034b	1.854	0.449	2.103	1.182	2.170	2.181	2.328	0.972	1.386	1.294	2.742	2.592	2.283	2.951
bdc1606	1.854	0.449	2.101	1.182	2.170	2.181	2.329	0.973	1.386	1.294	2.742	2.589	2.283	2.951
dc5a918	1.854	0.449	2.103	1.181	2.170	2.181	2.329	0.973	1.386	1.294	2.742	2.589	2.283	2.951