Revert "net: check if protocol extracted by virtio_net_hdr_set_proto is correct"

This reverts commit 54ef8243 which is
commit 924a9bc3 upstream.

This breaks the ABI and is not needed in the android-4.19-stable branch
as the issue it was added for is not relevant here.

Bug: 161946584
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I0a0453de60f4a614448cc62736eb32681277a6e8