[PATCH] ppc64: Fix PCI hotplug

pSeries_irq_bus_setup is marked __devinit but references s7a_workaround
which is marked __initdata.

Depending on who got the memory for s7a_workaround (and if the value was
now positive), it was possible for PCI hotplugged devices to have 3
subtracted from their interrupt number.  This would happen randomly and
caused me much confusion :)

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>