The EOL of NuttX is configurable (CR/LF/CRLF), the implementation
of getline in NuttX need CR or LF as line delimiter(CRLF not supported).
Then we should use readline for better compatibility.
Signed-off-by: Huang Qi <huangqi3@xiaomi.com>
Co-authored-by: Huang Qi <huangqi3@xiaomi.com>