spi: Add Kconfig menu entry

Added Kconfig menu ... endmenu enties for spi support.

Signed-off-by: Jagan Teki <jteki@openedev.com>
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index fbff707..913951f 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -1,3 +1,5 @@
+menu "SPI Support"
+
 config DM_SPI
 	bool "Enable Driver Model for SPI drivers"
 	depends on DM
@@ -59,3 +61,5 @@
 	  Enable the Zynq SPI driver. This driver can be used to
 	  access the SPI NOR flash on platforms embedding this Zynq
 	  SPI IP core.
+
+endmenu # menu "SPI Support"