V4L/DVB (3399): ELSA EX-VISION 500TV: fix incorrect PCI subsystem ID

- ELSA EX-VISION 500TV was incorrectly programmed to have the same
  subsystem ID as ELSA EX-VISION 300TV, (1048:226b)
- This changeset replaces the incorrect subsystem ID (1048:226b)
  with the correct one (1048:226a) for the ELSA EX-VISION 500TV.

Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>