Just like download_submodule() does, fixed warings when run
bb.fetch2.Fetch([url], d) in process_submodules' function:
WARNING: grpc-native-1.50.0-r0 do_fetch: URL: gitsm://github.com/abseil/abseil-cpp.git;protocol=https;name=third_party/abseil-cpp;subpath=third_party/abseil-cpp does not set any branch parameter. The future default branch used by tools and repositories is uncertain and we will therefore soon require this is set in all git urls.
(Bitbake rev: 0ed7c75eb0508a1f699f47d7f22d559501865f61)
Signed-off-by: Robert Yang <liezhi.yang@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
80e70e669f