Fail early if configuration module can not initialize properly
In the case that the config module cannot load the driver for libconfig or yaml,
currently, there might be a cascade of errors that are difficult for users to
understand. For instance (partially redacted for clarity):
[CONFIG] Error calling dlopen(libparams_libconfig.so): libparams_libconfig.so: cannot open shared object file: No such file or directory
[CONFIG] config module "libconfig" couldn't be loaded
[CONFIG] config_get, section log_config skipped, config module not properly initialized
[LOG] init aborted, configuration couldn't be performed
[CONFIG] config_get, section (null) skipped, config module not properly initialized
[CONFIG] /home/francesco/openairinterface5g/common/config/config_userapi.c 68 nfapi has no processed integer availablle
[CONFIG] config_get, section (null) skipped, config module not properly initialized
Assertion (get_softmodem_params()->default_pdu_session_id == -1) failed!
In get_common_options() /home/francesco/openairinterface5g/executables/softmodem-common.c:161
Use uicc0.pdu_sessions.[0].id to change the requested PDU session ID (is 0)
Here, the error is the missing shared object, but a user is more likely to look
at the last error instead of the first.
This commit addresses it by checking early for CONFIG_ISFLAGSET(CONFIG_ABORT),
and stopping if it is set. Additionally changes include making functions static,
removing late CONFIG_ISFLAGSET() checks, and the CONFIG_ISFLAGSET() in
load_configmodule(), because at that time "uniqCfg" is not set yet and thus does
not do anything (this is likely a regression of an earlier cleanup).
See-also: f50d5f5a ("make multiple config instead of one implicit global")