staging: easycap: kill EASYCAP_NEEDS_CARD_CREATE

for in-tree driver we can use snd_card_create
for backports to older kernels this can be easily wrapped

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>