cxgb4: dont touch blocked freelist bitmap after free

When adapter init fails, the blocked freelist bitmap is already freed
up and should not be touched. So, move the bitmap zeroing closer to
where it was successfully allocated. Also handle adapter init failure
unwind path immediately and avoid setting up RDMA memory windows.

Fixes: 5b377d11 ("cxgb4: Add debugfs facility to inject FL starvation")
Signed-off-by: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>