am33xx: Add support, update omap3 McSPI driver

Signed-off-by: Tom Rini <trini@ti.com>
diff --git a/drivers/spi/omap3_spi.c b/drivers/spi/omap3_spi.c
index 9346c0b..47f9e56 100644
--- a/drivers/spi/omap3_spi.c
+++ b/drivers/spi/omap3_spi.c
@@ -86,15 +86,21 @@
 	case 0:
 		ds->regs = (struct mcspi *)OMAP3_MCSPI1_BASE;
 		break;
+#ifdef OMAP3_MCSPI2_BASE
 	case 1:
 		ds->regs = (struct mcspi *)OMAP3_MCSPI2_BASE;
 		break;
+#endif
+#ifdef OMAP3_MCSPI3_BASE 
 	case 2:
 		ds->regs = (struct mcspi *)OMAP3_MCSPI3_BASE;
 		break;
+#endif
+#ifdef OMAP3_MCSPI4_BASE
 	case 3:
 		ds->regs = (struct mcspi *)OMAP3_MCSPI4_BASE;
 		break;
+#endif
 	default:
 		printf("SPI error: unsupported bus %i. \
 			Supported busses 0 - 3\n", bus);