memory: Document flatview_for_each_range()

Add a documentation comment describing flatview_for_each_range().

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20210318174823.18066-3-peter.maydell@linaro.org
1 file changed