cr-restore: optimize {loginuid,oom_score_adj} restoring
cr-restore: optimize {loginuid,oom_score_adj} restoring

1. Use PROC_SELF instead pid as prepare_pid_* used on restore only to
set value to current process.
2. Do not set default values.

Signed-off-by: Dmitry Safonov <5aea3f9692c8a01793193334616ae8fad2bc748a@odin.com>
Signed-off-by: Pavel Emelyanov <c9a32589e048e044184536f7ac71ef92fe82df3e@parallels.com>

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