media: ddbridge, cxd2099: include guard, fix unneeded NULL init, strings

Three really tiny minors in this single commit which all on their own
would just clutter up the commit history unnecessarily:

* ddbridge-regs.h is lacking an include guard. Add it.
* Fix an unnecessary NULL initialisation in ddbridge-ci. The declaration
  of the ci struct ptr is immediately followed by kzalloc().
* Clarify that the CXD2099AR is a Sony device in the cxd2099 driver at a
  few places including Kconfig.

Signed-off-by: Daniel Scheller <d.scheller@gmx.net>
Acked-by: Jasmin Jessich <jasmin@anw.at>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

drivers/media/pci/ddbridge/ddbridge-ci.c

@@ -164,7 +164,7 @@ static struct dvb_ca_en50221 en_templ = {
 
 static void ci_attach(struct ddb_port *port)
 {
-	struct ddb_ci *ci = NULL;
+	struct ddb_ci *ci;
 
 	ci = kzalloc(sizeof(*ci), GFP_KERNEL);
 	if (!ci)