dt-bindings: reset: oxnas: Update for OX820

Add new compatible string for reset and sys-ctrl for the Oxford
Semiconductor OX820 Support.
Drop the OX810SE indices since they moved in a dedicated include file.

Signed-off-by: Neil Armstrong <[e-mail]>
Acked-by: Rob Herring <[e-mail]>
Signed-off-by: Philipp Zabel <[e-mail]>

Documentation/devicetree/bindings/reset/oxnas,reset.txt

···
 controller binding usage.
 
 Required properties:
-- compatible: Should be "oxsemi,ox810se-reset"
+- compatible: For OX810SE, should be "oxsemi,ox810se-reset"
+	      For OX820, should be "oxsemi,ox820-reset"
 - #reset-cells: 1, see below
 
 Parent node should have the following properties :
-- compatible: Should be "oxsemi,ox810se-sys-ctrl", "syscon", "simple-mfd"
+- compatible: For OX810SE, should be :
+			"oxsemi,ox810se-sys-ctrl", "syscon", "simple-mfd"
+	      For OX820, should be :
+			"oxsemi,ox820-sys-ctrl", "syscon", "simple-mfd"
 
-For OX810SE, the indices are :
- - 0 : ARM
- - 1 : COPRO
- - 2 : Reserved
- - 3 : Reserved
- - 4 : USBHS
- - 5 : USBHSPHY
- - 6 : MAC
- - 7 : PCI
- - 8 : DMA
- - 9 : DPE
- - 10 : DDR
- - 11 : SATA
- - 12 : SATA_LINK
- - 13 : SATA_PHY
- - 14 : Reserved
- - 15 : NAND
- - 16 : GPIO
- - 17 : UART1
- - 18 : UART2
- - 19 : MISC
- - 20 : I2S
- - 21 : AHB_MON
- - 22 : UART3
- - 23 : UART4
- - 24 : SGDMA
- - 25 : Reserved
- - 26 : Reserved
- - 27 : Reserved
- - 28 : Reserved
- - 29 : Reserved
- - 30 : Reserved
- - 31 : BUS
+Reset indices are in dt-bindings include files :
+- For OX810SE: include/dt-bindings/reset/oxsemi,ox810se.h
+- For OX820: include/dt-bindings/reset/oxsemi,ox820.h
 
 example: