buildscripts: Use "all" protobuf download to avoid ./autogen.sh
buildscripts: Use "all" protobuf download to avoid ./autogen.sh

This cuts ~20 seconds from the build time and avoids the need to have
autoconf and libtool installed. This is the "normal" way to build
protobuf.

dapengzhang0/grpc-java,ejona86/grpc-java,stanley-cheung/grpc-java,zhangkun83/grpc-java,dapengzhang0/grpc-java,grpc/grpc-java,zhangkun83/grpc-java,carl-mastrangelo/grpc-java,carl-mastrangelo/grpc-java,stanley-cheung/grpc-java,ejona86/grpc-java,elandau/grpc-java,grpc/grpc-java,ejona86/grpc-java,stanley-cheung/grpc-java,dapengzhang0/grpc-java,carl-mastrangelo/grpc-java,stanley-cheung/grpc-java,elandau/grpc-java,grpc/grpc-java,carl-mastrangelo/grpc-java,elandau/grpc-java,elandau/grpc-java,dapengzhang0/grpc-java,zhangkun83/grpc-java,grpc/grpc-java,ejona86/grpc-java,zhangkun83/grpc-java