pci_alloc_msi is always called, is this bad?

[Sean Bruno]

I was looking at the recent thread on -stable about mfi(4) and I noted
that it appears, if I'm not mistaken, mfi_pci.c::pci_alloc_msi() is
*always* invoked regardless of the mfi_msi tuneable.  We just ignore the
allocated MSI by not setting sc->mfi_irq_rid.  Is that harmful?

------------------------------------------------------------------------
240         /* Allocate IRQ resource. */
241         sc->mfi_irq_rid = 0;
242         count = 1;
243         if (mfi_msi && pci_alloc_msi(sc->mfi_dev, &count) == 0) {
244                 device_printf(sc->mfi_dev, "Using MSI\n");
245                 sc->mfi_irq_rid = 1;
246         }


------------------------------------------------------------------------
I would have thought that this would be more correct, avoid calling
pci_alloc_msi() if mfi_msi isn't set in the first place.
------------------------------------------------------------------------
	sc->mfi_irq_ird = 0;
	count = 1;
	ret = 0
	if(mfi_msi)
		ret = pci_alloc_msi(sc->mfi_dev, &count);

	if (!ret) {
		device_printf(sc->mfi_dev, "Using MSI\n");
		sc->mfi_irq_rid = 1;
	}
------------------------------------------------------------------------

Sean
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