initscripts: add function log_success_msg/log_failure_msg/log_warning_msg

initscripts: add function log_success_msg/log_failure_msg/log_warning_msg

* add function log_success_msg/log_failure_msg/log_warning_msg, some
packages still use these functions, like mariadb, refer [1], without
these function, with sysV init manager, mariadb will report error:

root@qemux86-64:~# /etc/init.d/mysqld status
/etc/init.d/mysqld: line 383: log_success_msg: command not found

* remove RCONFLICTS with lsbinitscripts, LSB support already remove in
  [2]

[1] https://github.com/MariaDB/server/blob/main/support-files/mysql.server.sh#L104
[2] https://git.openembedded.org/openembedded-core/commit/?id=fb064356af615d67d85b65942103bf943d84d290
[3] https://refspecs.linuxbase.org/LSB_4.0.0/LSB-Core-generic/LSB-Core-generic/iniscrptfunc.html

Signed-off-by: Changqing Li <changqing.li@windriver.com>
Signed-off-by: Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>