Revert "LU-3319 procfs: move osp proc handling to seq_files"

This seems to be causing issues like LU-45-13 and LU-4510
This reverts commit a97e4898ad9e0b65f457b01bdfa954f7d7cd272d.

Change-Id: I6066a255ded24dbdb76b4804e82a377f1069af5f
Reviewed-on: http://review.whamcloud.com/8931
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>
Tested-by: Oleg Drokin <oleg.drokin@intel.com>