revert bab65e48cb064 PCI/MSI Sanitize MSI-X checks

[David Laight]

The change in bab65e48cb064 breaks pci_enable_msix_range().
The intent is to optimise the sanity checks, but it is
somewhat overenthusiastic.

The interface allows you to ask for a lot of vectors and
returns the number that were allocated.
However, after the change, you can't request a vector
that is higher than the largest the hardware supports.
Which makes that rather pointless.

So code like:
	for (i = 0; i < 16; i++)
		msix_tbl[i].entry = i;
	nvec = pci_enable_msix_range(dev, msix_tbl, 1, 16);
Now returns -22 if the hardware only supports 8 interrupts.

Previously it returned 8.

I can fix my driver, but I suspect that any code that relies
on a smaller number of vectors being returned is now broken.

	David

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