Config options --reconfig_file and --rbconfig-file have been introduced
to modify the filenames of reconfig.raw and rbconfig.raw (e.g., in the
case of multiple UEs). These filen*ames* were to be prepended with
--rrc_config_path to set the path. In summary, three options were
necessary, when two are sufficient.

In this commit, change to the options --reconfig-file and
--rbconfig-file (slight change for harmonization with other options,
which mostly use dashes) to give the full path to the corresponding
files, and avoid to surprise users who would not expect to have three
options.

--rrc_config_path has been deprecated and an error will be printed if a
user attempts to use it.