Fix branch name for repo init command

As node-red branch does not exist anymore we have to use master branch
during repo initialization

README.rst

@@ -37,7 +37,7 @@ Make sure that git is setup properly with the following commands below:
 Initialize the repo with the master branch of the repository with the following commands:
     - *mkdir vesta-gateway-bsp*
     - *cd vesta-gateway-bsp*
-    - *repo init -u https://git.rigado.com/vesta/board-support-package -b node-red*
+    - *repo init -u https://git.rigado.com/vesta/board-support-package -b master*
     - *repo sync -c -j1*
 
     NOTE: without -j1 repo will appear to lock up when it is actually asking for your user name.