regulator: pbias: Add additional compatible flags

The driver was developed with references for more than just
dra7, but never included.  At least for omap3, this appears
to be functional.

Signed-off-by: Adam Ford <aford173@gmail.com>

drivers/power/regulator/pbias_regulator.c

@@ -108,6 +108,10 @@ static struct dm_pmic_ops pbias_ops = {
 
 static const struct udevice_id pbias_ids[] = {
 	{ .compatible = "ti,pbias-dra7" },
+	{ .compatible = "ti,pbias-omap2" },
+	{ .compatible = "ti,pbias-omap3" },
+	{ .compatible = "ti,pbias-omap4" },
+	{ .compatible = "ti,pbias-omap5" },
 	{ }
 };