OMAPDSS: tpo-td043: remove platform_enable/disable callbacks

The tpo-td043 panel driver now manages the gpios required to configure the panel.
This was previously done in omap_dss_device's platform_enable/disable callbacks
defined in board files using this panel.

All the board files using this panel now pass the gpio information as platform
data via the panel_tpo_td043_data struct, which is needed by the panel driver to
configure the gpios connected to the panel. Hence, the platform_enable/disable
ops can be safely removed now.

Signed-off-by: Archit Taneja <archit@ti.com>