dynamic_debug: Convert printks to pr_<level>

Add pr_fmt(fmt) with __func__.
Converts "ddebug:" prefix to "dynamic_debug:".

Most likely the if (verbose) outputs could
also be converted from pr_info to pr_debug.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>