IB/{hfi1, rdmavt}: Fix memory leak in hfi1_alloc_devdata() upon failure

When allocating device data, if there's an allocation failure, the
already allocated memory won't be freed such as per-cpu counters.

Fix memory leaks in exception path by creating a common reentrant
clean up function hfi1_clean_devdata() to be used at driver unload
time and device data allocation failure.

To accomplish this, free_platform_config() and clean_up_i2c() are
changed to be reentrant to remove dependencies when they are called
in different order. This helps avoid NULL pointer dereferences
introduced by this patch if those two functions weren't reentrant.

In addition, set dd->int_counter, dd->rcv_limit,
dd->send_schedule and dd->tx_opstats to NULL after they're freed in
hfi1_clean_devdata(), so that hfi1_clean_devdata() is fully reentrant.

Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Sebastian Sanchez <sebastian.sanchez@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>