MINOR: cfgparse/log: remove leftover dead code

MINOR: cfgparse/log: remove leftover dead code

Remove development leftover introduced by commit 15e9c7da6 ("MINOR: log:
add log-profile parsing logic").

Indeed, since "log-profile" section keyword is registered via
REGISTER_CONFIG_SECTION() macro, it is not relevant to declare it in
common_kw_list[] from cfgparse-global.c. All it does is that it could
confuse the user by suggesting him to use "log-profile" inside a global
section when trying to find a best match in cfg_parse_global().