staging: lustre: ptlrpc: print times in microseconds

report times and time diffs in seconds.microseconds instead of seconds

Signed-off-by: Bob Glosman <bob.glossman@intel.com>
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-7733
Reviewed-on: http://review.whamcloud.com/18335


Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Minh Diep <minh.diep@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: James Simmons <jsimmons@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>