drm: extra printk() wrapper macros

We had only DRM_INFO() and DRM_ERROR(), whereas the underlying printk()
provides several other useful intermediate levels such as NOTICE and
WARNING. So this patch fills out the set by providing both regular and
once-only macros for each of the levels INFO, NOTICE, and WARNING, using
a common underlying macro that does all the token-pasting.

DRM_ERROR is unchanged, as it's not just a printk wrapper.

v2:
    Fix whitespace, missing ## (Eric Engestrom)

Signed-off-by: Dave Gordon <david.s.gordon@intel.com>
Reviewed-by: Eric Engestrom <eric.engestrom@imgtec.com>
Cc: dri-devel@lists.freedesktop.org
Acked-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>