[RFC][PATCH v9 2/3] perf config: Reimplement perf_config() adding perf_config_init() and perf_config_finish()

Many sub-commands use perf_config() so 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

[RFC][PATCH v9 2/3] perf config: Reimplement perf_config() adding perf_config_init() and perf_config_finish()

Many sub-commands use perf_config() so 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