atm: idt77252: fix a memleak in open_card_ubr0

When alloc_scq fails, card->vcs[0] (i.e. vc) should be freed. Otherwise,
in the following call chain:

idt77252_init_one
  |-> idt77252_dev_open
        |-> open_card_ubr0
              |-> alloc_scq [failed]
  |-> deinit_card
        |-> vfree(card->vcs);

card->vcs is freed and card->vcs[0] is leaked.

Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Signed-off-by: Zhipeng Lu <alexious@zju.edu.cn>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>