drm: remove unneeded break

A break is not needed if it is preceded by a return or break

Signed-off-by: Tom Rix <trix@redhat.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20201019163115.25814-1-trix@redhat.com