README: Add README.md with CI kernel build status tags

This is a copy of README with the tags added.

You can not delete the file README as then checkpatch complains
you aren't in a kernel tree.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>

diff --git a/README.md b/README.md
new file mode 100644 (file)
index 0000000..7be840e
--- /dev/null
+++ b/README.md
@@ -0,0 +1,30 @@
+Linux kernel
+============
+
+There are several guides for kernel developers and users. These guides can
+be rendered in a number of formats, like HTML and PDF. Please read
+Documentation/admin-guide/README.rst first.
+
+In order to build the documentation, use ``make htmldocs`` or
+``make pdfdocs``.  The formatted documentation can also be read online at:
+
+    https://www.kernel.org/doc/html/latest/
+
+There are various text files in the Documentation/ subdirectory,
+several of them using the Restructured Text markup notation.
+
+Please read the Documentation/process/changes.rst file, as it contains the
+requirements for building and running the kernel, and information about
+the problems which may result by upgrading your kernel.
+
+Build status for rpi-5.15.y:
+[![Pi kernel build tests](https://github.com/raspberrypi/linux/actions/workflows/kernel-build.yml/badge.svg?branch=rpi-5.15.y)](https://github.com/raspberrypi/linux/actions/workflows/kernel-build.yml)
+[![dtoverlaycheck](https://github.com/raspberrypi/linux/actions/workflows/dtoverlaycheck.yml/badge.svg?branch=rpi-5.15.y)](https://github.com/raspberrypi/linux/actions/workflows/dtoverlaycheck.yml)
+
+Build status for rpi-6.1.y:
+[![Pi kernel build tests](https://github.com/raspberrypi/linux/actions/workflows/kernel-build.yml/badge.svg?branch=rpi-6.1.y)](https://github.com/raspberrypi/linux/actions/workflows/kernel-build.yml)
+[![dtoverlaycheck](https://github.com/raspberrypi/linux/actions/workflows/dtoverlaycheck.yml/badge.svg?branch=rpi-6.1.y)](https://github.com/raspberrypi/linux/actions/workflows/dtoverlaycheck.yml)
+
+Build status for rpi-6.4.y:
+[![Pi kernel build tests](https://github.com/raspberrypi/linux/actions/workflows/kernel-build.yml/badge.svg?branch=rpi-6.4.y)](https://github.com/raspberrypi/linux/actions/workflows/kernel-build.yml)
+[![dtoverlaycheck](https://github.com/raspberrypi/linux/actions/workflows/dtoverlaycheck.yml/badge.svg?branch=rpi-6.4.y)](https://github.com/raspberrypi/linux/actions/workflows/dtoverlaycheck.yml)