tg3: Hold tp->lock before calling tg3_halt() from tg3_init_one()

tg3_init_one() calls tg3_halt() without tp->lock despite its assumption
and causes deadlock.
If lockdep is enabled, a warning like this shows up before the stall:

  [ BUG: bad unlock balance detected! ]
  3.19.0test #3 Tainted: G            E
  -------------------------------------
  insmod/369 is trying to release lock (&(&tp->lock)->rlock) at:
  [<ffffffffa02d5a1d>] tg3_chip_reset+0x14d/0x780 [tg3]
  but there are no more locks to release!

tg3_init_one() doesn't call tg3_halt() under normal situation but
during kexec kdump I hit this problem.

Fixes: 932f19de ("tg3: Release tp->lock before invoking synchronize_irq()")
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/tg3.c

@@ -17855,8 +17855,10 @@ static int tg3_init_one(struct pci_dev *pdev,
 	 */
 	if ((tr32(HOSTCC_MODE) & HOSTCC_MODE_ENABLE) ||
 	    (tr32(WDMAC_MODE) & WDMAC_MODE_ENABLE)) {
+		tg3_full_lock(tp, 0);
 		tw32(MEMARB_MODE, MEMARB_MODE_ENABLE);
 		tg3_halt(tp, RESET_KIND_SHUTDOWN, 1);
+		tg3_full_unlock(tp);
 	}
 
 	err = tg3_test_dma(tp);