qed: potential overflow in qed_cxt_src_t2_alloc()

qed: potential overflow in qed_cxt_src_t2_alloc()

In the current code "ent_per_page" could be more than "conn_num" making
"conn_num" negative after the subtraction.  In the next iteration
through the loop then the negative is treated as a very high positive
meaning we don't put a limit on "ent_num".  It could lead to memory
corruption.

Fixes: a3c4cda2e12e ('qed: Initialize hardware for new protocols')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Yuval Mintz <Yuval.Mintz@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>