Change OAI license to CSSL v1.0 (and others)

- all RAN code, CI code, configuration files, dockerfiles, in CSSL v1.0
- all deployment code (openshift, charts, ancillary files like shell
  scripts), in MIT
- documentation in CC-BY-4.0
- exceptions might apply and are listed in NOTICE
- there is a new LICENSES folder with all licenses
- CONTRIBUTIONS.md has been updated accordingly

For automated changes based on OAI PL v1.1:

    perl -i~ -0pe 's/\/\*.*Licensed to the OpenAirInterface.*openairinterface.org\n#?/\/*\n * SPDX-License-Identifier: LicenseRef-CSSL-1.0\n/s' **/*.{c,h,cpp}
    perl -i~ -0pe 's/\/\*.*Licensed to the OpenAirInterface.*openairinterface.org\n#?/\/*\n * SPDX-License-Identifier: LicenseRef-CSSL-1.0\n/s' **/*.ts
    perl -i~ -0pe 's/<!--.*Licensed to the OpenAirInterface.*openairinterface.org\n.*-->/<!-- SPDX-License-Identifier: LicenseRef-CSSL-1.0 -->/s' **/*.xml

The rest (cmake, files with missing license, cmake) manually.

common/utils/LOG/DOC/addconsoletrace.md

@@ -1,3 +1,5 @@
+<!-- SPDX-License-Identifier: CC-BY-4.0 -->
+
 ### Adding console traces in oai code
 #### console messages macros
 ```C

common/utils/LOG/DOC/arch.md

@@ -1,3 +1,5 @@
+<!-- SPDX-License-Identifier: CC-BY-4.0 -->
+
 # logging facility source files
 
 The oai logging facility is implemented in two source files, located in [common/utils/LOG](LOG)

common/utils/LOG/DOC/configurelog.md

@@ -1,3 +1,5 @@
+<!-- SPDX-License-Identifier: CC-BY-4.0 -->
+
 ### Initializing and configuring the logging facility
 
 #### logging facility APIs

common/utils/LOG/DOC/devusage.md

@@ -1,3 +1,5 @@
+<!-- SPDX-License-Identifier: CC-BY-4.0 -->
+
 ### logging facility developer usage
 The logging facility objectives are
 1. provide a common console tracing mechanism

common/utils/LOG/DOC/log.md

@@ -1,3 +1,5 @@
+<!-- SPDX-License-Identifier: CC-BY-4.0 -->
+
 # OAI console logging facility
 
 oai includes a console logging facility that any component should use when writting informational or debugging messages to the softmodem or uesoftmodem stdout stream.

common/utils/LOG/DOC/lttng_logs.md

@@ -1,3 +1,5 @@
+<!-- SPDX-License-Identifier: CC-BY-4.0 -->
+
 # OAI gNB LTTng Tracing Setup Guide
 
 ## Overview

common/utils/LOG/DOC/rtusage.md

@@ -1,3 +1,5 @@
+<!-- SPDX-License-Identifier: CC-BY-4.0 -->
+
 ## configuring the logging facility
 The logging facility is fully configurable and it uses the [config module](../../../../common/config/DOC/config.md) to get its parameters at init time. The [telnet server](../../telnetsrv/DOC/telnetsrv.md) includes a set of commands which can be used to dynamically modify the logging facility behavior