UPSTREAM: binder: Validate the default binderfs device names.

Length of a binderfs device name cannot exceed BINDERFS_MAX_NAME.
This patch adds a check in binderfs_init() to ensure the same
for the default binder devices that will be created in every
binderfs instance.

Co-developed-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Hridya Valsaraju <hridya@google.com>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Hridya Valsaraju <hridya@google.com>

Bug: 136497735
(cherry picked from commit 028fb5822b76bc2e095b5c145d7bd263878d9e27)
Change-Id: I347a427690ae35c792ce15afc90151937b879ef7