staging: brcm80211: remove counting of allocated sk_buff packets

The function pkt_buf_get_skb and pkt_buf_free_skb were using struct
osl_info field pktalloced to maintain counter of buffers in use in
the driver. It was decided to remove this facility. The prototypes
of these functions have been modified and the calling code adapted.

Reviewed-by: Brett Rudley <brudley@broadcom.com>
Reviewed-by: Henry Ptasinski <henryp@broadcom.com>
Reviewed-by: Roland Vossen <rvossen@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>