spi/qspi: update binding information

These update binding information for ti qspi controller.
Signed-off-by: Sourav Poddar <sourav.poddar@ti.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

Documentation/devicetree/bindings/spi/ti_qspi.txt

@@ -3,6 +3,11 @@ TI QSPI controller.
 Required properties:
 - compatible : should be "ti,dra7xxx-qspi" or "ti,am4372-qspi".
 - reg: Should contain QSPI registers location and length.
+- reg-names: Should contain the resource reg names.
+	- qspi_base: Qspi configuration register Address space
+	- qspi_mmap: Memory mapped Address space
+	- (optional) qspi_ctrlmod: Control module Address space
+- interrupts: should contain the qspi interrupt number.
 - #address-cells, #size-cells : Must be present if the device has sub-nodes
 - ti,hwmods: Name of the hwmod associated to the QSPI
 
@@ -14,7 +19,8 @@ Example:
 
 qspi: qspi@4b300000 {
 	compatible = "ti,dra7xxx-qspi";
-	reg = <0x4b300000 0x100>;
+	reg = <0x47900000 0x100>, <0x30000000 0x3ffffff>;
+	reg-names = "qspi_base", "qspi_mmap";
 	#address-cells = <1>;
 	#size-cells = <0>;
 	spi-max-frequency = <25000000>;