ARM: OMAP2/3: VENC hwmods: Remove OCPIF_SWSUP_IDLE flag from VENC slave interface

The clocks for all DSS slave interfaces were recently changed to "dss_ick" on
OMAP2 and OMAP3, this clock can be autoidled by PRCM. The VENC interface
previously had "dss_54m_fck" as it's clock which couldn't be autoidled, and
hence the OCPIF_SWSUP_IDLE flag was needed.

Remove the OCPIF_SWSUP_IDLE flag from VENC interfaces as it's clock is
now "dss_ick".  This allows the PRCM hardware to autoidle the VENC
interface clocks when they are not active, rather than relying on the
software to do it, which can keep the interface clocks active
unnecessarily.

Signed-off-by: Archit Taneja <archit@ti.com>
[paul@pwsan.com: add a short description of the fix to the commit log]
Signed-off-by: Paul Walmsley <paul@pwsan.com>