system: Simplify the line ending option in cle/readline/vi/bas

[xiaoxiang781216]

Summary

it's easy to handle \n or \r\n ending correctly, so let's reduce the possible option to one(EOL_IS_CR).

Impact

The end line handling

Testing

Please ignore the follow false style alarm:

Error: /home/runner/work/incubator-nuttx-apps/incubator-nuttx-apps/apps/interpreters/bas/bas_fs.c:1872:4: error: Mixed case identifier found
Error: /home/runner/work/incubator-nuttx-apps/incubator-nuttx-apps/apps/interpreters/bas/bas_fs.c:1874:2: error: Mixed case identifier found
Error: /home/runner/work/incubator-nuttx-apps/incubator-nuttx-apps/apps/system/vi/vi.c:512:57: error: Multiple data definitions
Error: /home/runner/work/incubator-nuttx-apps/incubator-nuttx-apps/apps/system/vi/vi.c:513:54: error: Multiple data definitions