lnrpc: remove reference to GOPATH

As go modules allow us to build outside of the GOPATH, we shouldn't look for .proto imports there anymore.

lnrpc/gen_protos.sh

@@ -4,21 +4,18 @@ echo "Generating root gRPC server protos"
 
 # Generate the protos.
 protoc -I/usr/local/include -I. \
-       -I$GOPATH/src \
        -I$GOPATH/src/github.com/grpc-ecosystem/grpc-gateway/third_party/googleapis \
-       --go_out=plugins=grpc:. \
+       --go_out=plugins=grpc,paths=source_relative:. \
        rpc.proto
 
 # Generate the REST reverse proxy.
 protoc -I/usr/local/include -I. \
-       -I$GOPATH/src \
        -I$GOPATH/src/github.com/grpc-ecosystem/grpc-gateway/third_party/googleapis \
        --grpc-gateway_out=logtostderr=true:. \
        rpc.proto
 
 # Finally, generate the swagger file which describes the REST API in detail.
 protoc -I/usr/local/include -I. \
-       -I$GOPATH/src \
        -I$GOPATH/src/github.com/grpc-ecosystem/grpc-gateway/third_party/googleapis \
        --swagger_out=logtostderr=true:. \
        rpc.proto
@@ -30,8 +27,7 @@ do
     DIRECTORY=$(dirname ${file})
     echo "Generating protos from ${file}, into ${DIRECTORY}"
 
-    protoc -I/usr/local/include -I. \
-           -I$GOPATH/src \
-           --go_out=plugins=grpc:. \
+    protoc -I/usr/local/include -I.\
+           --go_out=plugins=grpc,paths=source_relative:. \
            ${file}
 done