Add a configuration option to enable Defy (MB525/MB526) related code.

Change-Id: Ic11089a43d8cca5f6d7ad944ae96518059669056
board-mapphone-panel: Make clear which changes are Defy related.

Change-Id: I76d1886bf3e18f906f70a763c1b0c78e990ccec5
panel-mapphone: More fixes plus minor code cleanup.

There were two more fixes needed:
* DSI high speed mode (omapdss_dsi_vc_enable_hs) cannot be enabled, when
  we're sending EDISCO commands. Otherwise we get SoT errors.
* mapphone_panel_display_on can only be called from framedone_cb for
  omap4 devices. On omap3 this causes a WARN_ON because DSI is doing
  work which requires interrupts to be disabled when we're calling
  mapphone_panel_display_on from framedone_cb. Since framedone_cb is
  running in interrupt context this causes errors.
  The fix is quite simple: We enable the display in mapphone_panel_power_on
  (right after the display is initialized). This might cause visual
  artifacts (for the boot time) but it's better than a non-working display.

The code was also cleaned up a bit and unneeded methods (from
newer/solana DSS) were commented. Comments were added wherever they
were needed.

Change-Id: Ib313f03a3d4ff01a9b88f213c90b3ef50a1acc3a