OMAP2, 3: DSS2: remove forced clk-disable from omap_dss_remove

As part of omap hwmod changes, DSS will not be the only controller of its
clocks. hwmod initialization also enables the interface clocks, and
manages them.
So, when DSS is built as a module, omap_dss_remove doesn't try to disable
all clocks that have a higher usecount.

Reviewed-by: Kevin Hilman <khilman@ti.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Sumit Semwal <sumit.semwal@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>