cpupower: Condense pstate enabled bit checks in decode_pstates()

mainline inclusion
from mainline-5.12-rc1-dontuse
commit 56a85eeb
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I4QQWF



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The enabled bit (bit 63) is common for all families so we can remove
the multiple enabled checks based on family and have a common check
for HW pstate enabled.

Signed-off-by: Nathan Fontenot <nathan.fontenot@amd.com>
Reviewed-by: Robert Richter <rrichter@amd.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: qinyu <qinyu16@huawei.com>
Reviewed-by: Chao Liu <liuchao173@huawei.com>
Reviewed-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>