sys/v4l2/: Renamed some properties to match the tuner interface naming.

sys/v4l2/: Renamed some properties to match the tuner interface naming.

Original commit message from CVS:
* sys/v4l2/gstv4l2object.c:
(gst_v4l2_object_install_properties_helper), (gst_v4l2_object_new),
(gst_v4l2_object_set_property_helper),
(gst_v4l2_object_get_property_helper), (gst_v4l2_set_defaults):
* sys/v4l2/gstv4l2object.h:
* sys/v4l2/gstv4l2src.c: (gst_v4l2src_class_init),
(gst_v4l2src_create):
* sys/v4l2/gstv4l2tuner.c: (gst_v4l2_tuner_contains_channel),
(gst_v4l2_tuner_list_channels),
(gst_v4l2_tuner_set_channel_and_notify),
(gst_v4l2_tuner_get_channel), (gst_v4l2_tuner_contains_norm),
(gst_v4l2_tuner_list_norms), (gst_v4l2_tuner_set_norm_and_notify),
(gst_v4l2_tuner_get_norm):
* sys/v4l2/v4l2_calls.c: (gst_v4l2_get_capabilities),
(gst_v4l2_fill_lists), (gst_v4l2_empty_lists):
* sys/v4l2/v4l2src_calls.c: (gst_v4l2src_get_fps):
Renamed some properties to match the tuner interface naming.