Add @since to osl_areCommandArgsSet.

Change-Id: Ib2d033f975a9b5bf7b667fd80e495d8f043faff0
Mark osl_areCommandArgsSet as internal only.

Change-Id: Iac97290738088bd1ce7469ffee773994e7653efc
osl_areCommandArgsSet: ensure mutexes locked when accessing data.

Change-Id: I6b1f10e74aafc47e5618290d92087563c60e3c49