fpga: dfl: fme: add performance reporting support

This patch adds support for performance reporting private feature
for FPGA Management Engine (FME). Actually it supports 4 categories
performance counters, 'clock', 'cache', 'iommu' and 'fabric', user
could read the performance counter via exposed sysfs interfaces.
Please refer to sysfs doc for more details.

Signed-off-by: Luwei Kang <luwei.kang@intel.com>
Signed-off-by: Xu Yilun <yilun.xu@intel.com>
Signed-off-by: Wu Hao <hao.wu@intel.com>
7 files changed