Add build doc for Fabric-Admin and Fabric-Bridge-App

Author: yufengwangca

examples/fabric-admin/README.md

@@ -0,0 +1,48 @@
+# Matter Fabric Administrator Example
+
+An example application that which supports synchronization of devices between fabrics.
+
+
+---
+
+-   [Building the Example Application](#building-the-example-application)
+
+---
+
+## Building the Example Application
+
+For Linux host example:
+
+```
+./scripts/examples/gn_build_example.sh examples/fabric-admin out/debug/standalone chip_config_network_layer_ble=false 'import("//with_pw_rpc.gni")'
+```
+
+For Raspberry Pi 4 example:
+
+### Pull Docker Images
+```
+docker pull connectedhomeip/chip-build-vscode:latest
+```
+
+### Run docker
+```
+docker run -it -v ~/connectedhomeip:/var/connectedhomeip connectedhomeip/chip-build-vscode:latest /bin/bash
+```
+### Build
+```
+cd /var/connectedhomeip
+
+git config --global --add safe.directory /var/connectedhomeip
+git config --global --add safe.directory /var/connectedhomeip/third_party/pigweed/repo
+git config --global --add safe.directory /var/connectedhomeip/examples/common/QRCode/repo
+
+./scripts/run_in_build_env.sh \
+ "./scripts/build/build_examples.py \
+    --target linux-arm64-fabric-admin-clang-rpc \
+    build"
+```
+
+###  Transfer the fabric-admin binary to a Raspberry Pi
+```
+scp ./fabric-admin ubuntu@xxx.xxx.xxx.xxx:/home/ubuntu
+```

examples/fabric-bridge-app/README.md

@@ -0,0 +1,48 @@
+# Matter Fabric Bridge Example
+
+An Fabric Bridge example application that which supports synchronization of devices between fabrics.
+
+
+---
+
+-   [Building the Example Application](#building-the-example-application)
+
+---
+
+## Building the Example Application
+
+For Linux host example:
+
+```
+./scripts/examples/gn_build_example.sh examples/fabric-bridge-app/linux out/debug/standalone chip_config_network_layer_ble=false 'import("//with_pw_rpc.gni")'
+```
+
+For Raspberry Pi 4 example:
+
+### Pull Docker Images
+```
+docker pull connectedhomeip/chip-build-vscode:latest
+```
+
+### Run docker
+```
+docker run -it -v ~/connectedhomeip:/var/connectedhomeip connectedhomeip/chip-build-vscode:latest /bin/bash
+```
+### Build
+```
+cd /var/connectedhomeip
+
+git config --global --add safe.directory /var/connectedhomeip
+git config --global --add safe.directory /var/connectedhomeip/third_party/pigweed/repo
+git config --global --add safe.directory /var/connectedhomeip/examples/common/QRCode/repo
+
+./scripts/run_in_build_env.sh \
+ "./scripts/build/build_examples.py \
+    --target linux-arm64-fabric-bridge-no-ble-clang-rpc \
+    build"
+```
+
+###  Transfer the fabric-bridge-app binary to a Raspberry Pi
+```
+scp ./fabric-bridge-app ubuntu@xxx.xxx.xxx.xxx:/home/ubuntu
+```