Add ext4l_read() function to read file contents. The function resolves
the path to an inode, then reads the file block by block using
ext4_bread() and copies the data to the output buffer.
Signed-off-by: Simon Glass <sjg@chromium.org>
Co-developed-by: Claude Opus 4.5 <noreply@anthropic.com>
Signed-off-by: Simon Glass <simon.glass@canonical.com>