README.md: Rename repository from meta-ohos to oniro

The repository will be renamed and its path will change. For now we only
advertise the new repository name: oniro. Additional changes will come
when it's path will also change.

Signed-off-by: Andrei Gherzan <andrei.gherzan@huawei.com>

README.md

@@ -4,11 +4,11 @@ SPDX-FileCopyrightText: Huawei Inc.
 SPDX-License-Identifier: CC-BY-4.0
 -->
 
-# meta-ohos
+# Oniro
 
-**meta-ohos** is a collection of bitbake layers that implement the build system
-support in Oniro Project. The build system documentation is available in the
-`docs` subdirectory.
+**oniro** repository is a collection of bitbake layers that implement the build
+system support in Oniro Project. The build system documentation is available in
+the `docs` subdirectory.
 
 ## Contributing