Teach build to work on alpine linux protobuf tools

build

@@ -317,9 +317,13 @@ fi
 
 # Do Protobufs if needed
 if [ -n "$Protobufs" ]; then
+    set +e
     slick=$Hostbindir/protoc-gen-gogoslick
     slicksrc=github.com/gogo/protobuf/protoc-gen-gogoslick
-    pc=$(type -p protoc)
+    for pc in protoc protoc-c; do
+        pc=`which $pc`
+        [ -n "$pc" ] && break
+    done
 
     [ -z "$pc" ] && die "Need 'protoc' for building .."
 
@@ -340,6 +344,7 @@ if [ -n "$Protobufs" ]; then
             $e $pc --gogoslick_out=. $f || exit 1
         fi
     done
+    set -e
 fi
 
 repover="main.RepoVersion=$rev"