[Offload][NFC] Add offload subfolder and README (#77154)

The readme only states the goal and has links to further information,
e.g., our meetings.

---------

Co-authored-by: Shilei Tian <i@tianshilei.me>

Author: jdoerfert

offload/README.md

@@ -0,0 +1,20 @@
+# The LLVM/Offload Subproject
+
+The Offload subproject aims at providing tooling, runtimes, and APIs that allow
+users to execute code on accelerators or other "co-processors" that may or may
+not match the architecture of their "host". In the long run, all kinds of
+targets are in scope of this effort, including but not limited to: CPUs, GPUs,
+FPGAs, AI/ML accelerators, distributed resources, etc.
+
+The project is just starting and the design is still not ironed out. More
+content will show up here and on our webpage soon. In the meantime people are
+encouraged to participate in our meetings (see below) and check our
+[development board](https://github.com/orgs/llvm/projects/24/) as well as the
+discussions on [Discourse](https://discourse.llvm.org/tag/offload).
+
+# Meetings
+
+Every second Wednesday, 7:00 - 8:00am PT, starting Jan 24, 2024.
+Alternates with the OpenMP in LLVM meeting.
+[invite.ics](https://drive.google.com/file/d/1AYwKdnM01aV9Gv9k435ArEAhn7PAer7z/view?usp=sharing)
+[Meeting Minutes and Agenda](https://docs.google.com/document/d/1PAeEshxHCv22JDBCPA9GXGggLp0t7rsnD_jL04MBbzw/edit?usp=sharing)