cpufreq: interactive: fix cpufreq object duplicate creatation in sysfs

cpufreq: interactive: fix cpufreq object duplicate creatation in sysfs

[    4.216722] sysfs: cannot create duplicate filename '/devices/system/cpu/cpufreq'
[    4.233798] ------------[ cut here ]------------
[    4.244376] WARNING: at fs/sysfs/dir.c:31
[    4.253556]
[    4.256975] CPU: 3 PID: 1 Comm: swapper/0 Not tainted 4.4.0 #156
[    4.270730] Hardware name: Rockchip SDK tb board (DT)
[    4.282302] task: ffffffc039670000 ti: ffffffc039678000 task.ti: ffffffc039678000
[    4.299444] PC is at sysfs_warn_dup+0x5c/0x78
[    4.309422] LR is at sysfs_warn_dup+0x5c/0x78

Change-Id: Id21fe74dc082ec6c94fcb3e0cc11b78226549f7d
Fixes: bc68f6c4efbd ("cpufreq: interactive: build fixes for 4.4")
Signed-off-by: Rocky Hao <rocky.hao@rock-chips.com>