staging: rtl8723bs: tidy up error handling

staging: rtl8723bs: tidy up error handling

The check for if rtw_skb_alloc() fails is done twice and is written
in a confusing way.  Move the "if (!recvbuf->pskb)" right after
the allocation.  The "if (recvbuf->pskb)" check can now be deleted
and the code pulled in one tab.

Suggested-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Yihao Han <hanyihao@vivo.com>
Link: https://lore.kernel.org/r/20220408144442.17611-1-hanyihao@vivo.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>