[PATCH] i386/x86_64: FIX pci_enable_irq to set dev->irq to the irq number

In commit ace80ab7 I removed the weird
logic that used the vector number as the irq number when MSI was
defined.  However pci_enable_irq was using a different test in the
io_apic_assign_irqs path and I missed it :(

This patch removes the wrong code so no one hits this problem.

This code is only active when a specific set of boot command line
parameters is specified which likely explains why no one has notices
this earlier.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>