[PATCH] hostap: Fix memory leak on PCI probe error path

The Coverity checker (CID: 659, 660) spotted this resource leak on
PCI probe error path. Free private data structure if pci_enable_device()
fails.

Signed-off-by: Jouni Malinen <jkmaline@cc.hut.fi>
Signed-off-by: John W. Linville <linville@tuxdriver.com>