drivers-core: make structured logging play nice with dynamic-debug

drivers-core: make structured logging play nice with dynamic-debug

commit af7f2158fdee9d7f55b793b09f8170a3391f889a upstream.

commit c4e00daaa96d3a0786f1f4fe6456281c60ef9a16 changed __dev_printk
in a way that broke dynamic-debug's ability to control the dynamic
prefix of dev_dbg(dev,..), but not dev_dbg(NULL,..) or pr_debug(..),
which is why it wasnt noticed sooner.

When dev==NULL, __dev_printk() just calls printk(), which just works.
But otherwise, it assumed that level was always a string like "<L>"
and just plucked out the 'L', ignoring the rest.  However,
dynamic_emit_prefix() adds "[tid] module:func:line:" to the string,
those additions all got lost.

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Acked-by: Jason Baron <jbaron@redhat.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>