This patch addresses the potential issue of uninitialized elements in
the argument vector returned by `lwp_get_command_line_args()`. The
previous implementation could leave `argv` in an inconsistent state
if certain errors occurred, leading to possible undefined behavior.
Changes:
- Replaced `rt_malloc()` with `rt_calloc()` to ensure `argv` is properly initialized.
- Added a consistent error handling path using `goto error_exit` to handle memory allocation failures and string copy errors.
- Ensured `lwp_free_command_line_args()` is called before returning on error, preventing potential memory leaks.
Signed-off-by: Shell <smokewood@qq.com>
564ca848f4