media: add SPDX headers to some files

Add SPDX headers and fix MODULE_LICENSE() when needed on
some files I co-authored.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
diff --git a/drivers/media/pci/cx88/cx88-video.c b/drivers/media/pci/cx88/cx88-video.c
index 3b49ebb..5256ad7 100644
--- a/drivers/media/pci/cx88/cx88-video.c
+++ b/drivers/media/pci/cx88/cx88-video.c
@@ -33,7 +33,7 @@
 
 MODULE_DESCRIPTION("v4l2 driver module for cx2388x based TV cards");
 MODULE_AUTHOR("Gerd Knorr <kraxel@bytesex.org> [SuSE Labs]");
-MODULE_LICENSE("GPL");
+MODULE_LICENSE("GPL v2");
 MODULE_VERSION(CX88_VERSION);
 
 /* ------------------------------------------------------------------ */