Gator deadlocks system on Linux 3.5

Linux 3.5 now contains a patch [1] which means context switch trace
points are called with the run-queue lock held, this means that such
tracepoints can't:

a. sleep
b. queue work on workqueues

This means that Gator is a bit stuffed as it is currently implemented
because gator_events_meminfo_read() wants to call si_meminfo() which can
sleep, so we can't call it (as the code currently tries to) and we also
can't use the alternative mechanism it uses when in_interrupt() returns
true of using a workqueue to do this call.

Note there are other places which will have a similar problems, e.g.
gator_events_net_read() and translate_app_process().

I'm pretty sure I have analysed this right, and I can't see a quick fix
for this. (And I don't understand the code enough to propose a slow
fix.)

[1] Patch 7fec1b57 "ARM: Remove __ARCH_WANT_INTERRUPTS_ON_CTXSW on
ASID-capable CPUs)"

Fix committed to gator git... http://git.linaro.org/gitweb?p=arm/ds5/gator.git;a=commit;h=2ccfda6ba471ba1722fe48d23767d9d024bd0750

And also in the ARM LT topic branch which gets pulled into linux-linaro-core-tracking

Bug only affects kernels 3.5 or newer, and vexpress was only platform on these newer kernels and contained the fix in the 12.07 release