0e9c88b170
Implement ext4l_exists() to check if a file or directory exists on the filesystem. This uses ext4l_resolve_path() to look up the path and returns 1 if found, 0 otherwise. Wire the function into fs_legacy.c and add a basic test. Co-developed-by: Claude Opus 4.5 <noreply@anthropic.com> Signed-off-by: Simon Glass <simon.glass@canonical.com>