rtlwifi: Modify rtl_pci_init to return 0 on success

Fixes problem where caller would think routine succeeded when it failed
leading to divide by zero panic.

Signed-off-by: Simon Graham <simon.graham@virtualcomputer.com>
Acked-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>