bnxt_en: Fix possible BUG() condition when calling pci_disable_msix().

When making configuration changes, the driver calls bnxt_close_nic()
and then bnxt_open_nic() for the changes to take effect.  A parameter
irq_re_init is passed to the call sequence to indicate if IRQ
should be re-initialized.  This irq_re_init parameter needs to
be included in the bnxt_reserve_rings() call.  bnxt_reserve_rings()
can only call pci_disable_msix() if the irq_re_init parameter is
true, otherwise it may hit BUG() because some IRQs may not have been
freed yet.

Fixes: 41e8d798

 ("bnxt_en: Modify the ring reservation functions for 57500 series chips.")
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>