OMAP: DSS2: DSI: Fix DSI PLL power bug

OMAP3630 has a HW bug causing DSI PLL power command POWER_ON_DIV (0x3)
to not work properly. The bug prevents us from enabling DSI PLL power
only to HS divider block.

This patch adds a dss feature for the bug and converts POWER_ON_DIV
requests to POWER_ON_ALL (0x2).

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
diff --git a/drivers/video/omap2/dss/dsi.c b/drivers/video/omap2/dss/dsi.c
index 5cf13f4..fe655b6 100644
--- a/drivers/video/omap2/dss/dsi.c
+++ b/drivers/video/omap2/dss/dsi.c
@@ -1059,6 +1059,11 @@
 {
 	int t = 0;
 
+	/* DSI-PLL power command 0x3 is not working */
+	if (dss_has_feature(FEAT_DSI_PLL_PWR_BUG) &&
+			state == DSI_PLL_POWER_ON_DIV)
+		state = DSI_PLL_POWER_ON_ALL;
+
 	REG_FLD_MOD(DSI_CLK_CTRL, state, 31, 30);	/* PLL_PWR_CMD */
 
 	/* PLL_PWR_STATUS */