dt-bindings: vendor-prefixes: add milkv/sophgo

Add new vendor strings to dt bindings.
These new vendor strings are used by
- SOPHGO's SG2042 SoC [1]
- Milk-V Pioneer board [2], which uses SG2042 chip.

Link: https://en.sophgo.com/product/introduce/sg2042.html [1]
Link: https://milkv.io/pioneer [2]

Reviewed-by: Guo Ren <guoren@kernel.org>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Acked-by: Chao Wei <chao.wei@sophgo.com>
Signed-off-by: Chen Wang <unicorn_wang@outlook.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>

Documentation/devicetree/bindings/vendor-prefixes.yaml

@@ -863,6 +863,8 @@ patternProperties:
     description: MikroElektronika d.o.o.
   "^mikrotik,.*":
     description: MikroTik
+  "^milkv,.*":
+    description: MilkV Technology Co., Ltd
   "^miniand,.*":
     description: Miniand Tech
   "^minix,.*":
@@ -1273,6 +1275,8 @@ patternProperties:
     description: Solomon Systech Limited
   "^sony,.*":
     description: Sony Corporation
+  "^sophgo,.*":
+    description: Sophgo Technology Inc.
   "^sourceparts,.*":
     description: Source Parts Inc.
   "^spansion,.*":