LU-629 ptlrpc: fix _debug_req to print opc/status

LU-629 ptlrpc: fix _debug_req to print opc/status

The 2.x _debug_req() function was changed in bug 16359/commit 5467a86021
to avoid problems with accessing unswabbed message buffers. Unfortunately,
this broke the printing of many/most _debug_req() messages, because it
didn't check whether swabbing was actually needed in the first place.

Also, in ptlrpc_expire_one_request() some extra debugging information was
added in bug 21636/commit 368689640 but never removed, making this common
message overly verbose.

Fix _debug_req() so that it prints opcode/flags/status, unless the
ptlrpc_body _needs_ to be swabbed, but isn't.  Also print out more
useful idenfifiers for the nodes (the obd_name and NID instead of
the connection UUID).  This removes some of the added verbosity from
ptlrpc_expire_one_request(), and most of the rest was already being
printed out (deadline, current, etc).

Change-Id: I88a78486becd19f5b38f5578e5cc30e649564908
Signed-off-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-on: http://review.whamcloud.com/1286
Tested-by: Hudson
Reviewed-by: Mikhail Pershin <tappro@whamcloud.com>
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Niu Yawei <niu@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>