[media] s5p-mfc: set capablity bus_info as required by VIDIOC_QUERYCAP

The driver doesn't set the struct v4l2_capability bus_info field so the
v4l2-compliance tool reports the following errors for VIDIOC_QUERYCAP:

Required ioctls:
                VIDIOC_QUERYCAP returned 0 (Success)
                fail: v4l2-compliance.cpp(304): string empty
                fail: v4l2-compliance.cpp(528): check_ustring(vcap.bus_info, sizeof(vcap.bus_info))
        test VIDIOC_QUERYCAP: FAIL

This patch fixes by setting the field in VIDIOC_QUERYCAP ioctl handler:

Required ioctls:
                VIDIOC_QUERYCAP returned 0 (Success)
        test VIDIOC_QUERYCAP: OK

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Kamil Debski <k.debski@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

drivers/media/platform/s5p-mfc/s5p_mfc_dec.c

@@ -267,7 +267,8 @@ static int vidioc_querycap(struct file *file, void *priv,
 
 	strncpy(cap->driver, dev->plat_dev->name, sizeof(cap->driver) - 1);
 	strncpy(cap->card, dev->plat_dev->name, sizeof(cap->card) - 1);
-	cap->bus_info[0] = 0;
+	snprintf(cap->bus_info, sizeof(cap->bus_info), "platform:%s",
+		 dev_name(&dev->plat_dev->dev));
 	/*
 	 * This is only a mem-to-mem video device. The capture and output
 	 * device capability flags are left only for backward compatibility

drivers/media/platform/s5p-mfc/s5p_mfc_enc.c

@@ -945,7 +945,8 @@ static int vidioc_querycap(struct file *file, void *priv,
 
 	strncpy(cap->driver, dev->plat_dev->name, sizeof(cap->driver) - 1);
 	strncpy(cap->card, dev->plat_dev->name, sizeof(cap->card) - 1);
-	cap->bus_info[0] = 0;
+	snprintf(cap->bus_info, sizeof(cap->bus_info), "platform:%s",
+		 dev_name(&dev->plat_dev->dev));
 	/*
 	 * This is only a mem-to-mem video device. The capture and output
 	 * device capability flags are left only for backward compatibility