infiniband: hfi1: fix a memory leak bug

In fault_opcodes_read(), 'data' is not deallocated if debugfs_file_get()
fails, leading to a memory leak. To fix this bug, introduce the 'free_data'
label to free 'data' before returning the error.

Signed-off-by: Wenwen Wang <wenwen@cs.uga.edu>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Acked-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Link: https://lore.kernel.org/r/1566156571-4335-1-git-send-email-wenwen@cs.uga.edu


Signed-off-by: Doug Ledford <dledford@redhat.com>