Add a check of the _log function with LOGL_FORCE_DEBUG flags, used to force the trace display. The trace should be displayed for all the level when flags have LOGL_FORCE_DEBUG bit is set, for any filter. Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com> Reviewed-by: Sean Anderson <seanga2@gmail.com> Reviewed-by: Simon Glass <sjg@chromium.org>