[PATCH v5 1/7] perf config: Introduce default_config_section and default_config_item for default config key-value pairs

When initializing default perf config values, we currently use values of actual type(int, bool, char *, etc.). For example, If there isn't user config value at ~/.perfconfig for 'annotate.use_offset' config variable, default value for it is 'true' bool type value in perf like below. At

[PATCH v5 1/7] perf config: Introduce default_config_section and default_config_item for default config key-value pairs

When initializing default perf config values, we currently use values of actual type(int, bool, char *, etc.). For example, If there isn't user config value at ~/.perfconfig for 'annotate.use_offset' config variable, default value for it is 'true' bool type value in perf like below. At