remove outdated README section about adapters

README.md

@@ -6,11 +6,6 @@
 [![Coverity](https://scan.coverity.com/projects/28213/badge.svg)](https://scan.coverity.com/projects/oneapi-src-unified-runtime)
 [![codecov.io](https://codecov.io/github/oneapi-src/unified-runtime/coverage.svg?branch=main)](https://codecov.io/github/oneapi-src/unified-runtime?branch=master)
 
-## Adapters
-Adapter implementations for Unified Runtime currently reside in the [SYCL repository](https://github.com/intel/llvm/tree/sycl/sycl/plugins/unified_runtime/ur). This branch contains scripts to automatically
-fetch and build them directly in the UR tree. The adapters are disabled by default,
-see cmake options for details.
-
 <!-- TODO: add general description and purpose of the project -->
 
 ## Table of contents