If the user is clearing the log buffer too slowly, we overflow. As this
is an expected condition, and the driver tries to handle it, reduce the
error message down to a notice.

Michal mentioned that another cause would be incorrect reset handling,
so we don't want to lose the notification entirely.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=110817Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190617100917.13110-1-chris@chris-wilson.co.uk