[PATCH v4 4/6] perf config: Reimplement perf_config() using perf_config_set__iter()

Everytime perf_config() is called, perf_config() always read config files. (i.e. user config '~/.perfconfig' and system config '$(sysconfdir)/perfconfig') But we need to use the config set that already contains all config key-value pairs to avoid this repetitive work reading the config files in

[PATCH v4 4/6] perf config: Reimplement perf_config() using perf_config_set__iter()

Everytime perf_config() is called, perf_config() always read config files. (i.e. user config '~/.perfconfig' and system config '$(sysconfdir)/perfconfig') But we need to use the config set that already contains all config key-value pairs to avoid this repetitive work reading the config files in