docs: dt: convert booting-without-of.txt to ReST format

- Add a SPDX header;
- Adjust document title;
- Adjust document and section titles;
- Some whitespace fixes and new line breaks;
- Mark literal blocks as such;
- Add table markups;
- Add it to devicetree/index.rst.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/8dce14af13f66cb8393c21b58f0693e667a7045f.1592918949.git.mchehab+huawei@kernel.orgSigned-off-by: Jonathan Corbet <corbet@lwn.net>

Documentation/arm/booting.rst

@@ -128,7 +128,7 @@ it.  The recommended placement is in the first 16KiB of RAM.
 
 The boot loader must load a device tree image (dtb) into system ram
 at a 64bit aligned address and initialize it with the boot data.  The
-dtb format is documented in Documentation/devicetree/booting-without-of.txt.
+dtb format is documented in Documentation/devicetree/booting-without-of.rst.
 The kernel will look for the dtb magic value of 0xd00dfeed at the dtb
 physical address to determine if a dtb has been passed instead of a
 tagged list.

Documentation/devicetree/index.rst

@@ -15,3 +15,4 @@ Open Firmware and Device Tree
    overlay-notes
 
    bindings/index
+   booting-without-of

Documentation/translations/zh_CN/arm/Booting

@@ -124,7 +124,7 @@ bootloader 必须传递一个系统内存的位置和最小值，以及根文件
 
 bootloader 必须以 64bit 地址对齐的形式加载一个设备树映像(dtb)到系统
 RAM 中，并用启动数据初始化它。dtb 格式在文档
-Documentation/devicetree/booting-without-of.txt 中。内核将会在
+Documentation/devicetree/booting-without-of.rst 中。内核将会在
 dtb 物理地址处查找 dtb 魔数值（0xd00dfeed），以确定 dtb 是否已经代替
 标签列表被传递进来。