IB/ipath: Don't call spin_lock_irq() from interrupt context

This patch fixes the problem reported by Bernd Schubert <bs@q-leap.de>
with kernel debug options enabled:

    BUG: at kernel/lockdep.c:1860 trace_hardirqs_on()

This was caused by using spin_lock_irq()/spin_unlock_irq() from
interrupt context.  Fix all the places that might be called from
interrupts to use spin_lock_irqsave()/spin_unlock_irqrestore().

Signed-off-by: Ralph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>