teach proto_c to look in the source directory for out of tree builds

(cherry picked from commit c0d4ff57961edfaf0713d9a215750cfa26f42548)

diff --git a/lib/dns/Makefile.in b/lib/dns/Makefile.in
index 4a8549ec4e08dae78df15d489fd5513235116947..068bbac6debb25cb766acdf7687ff62410f14e71 100644 (file)
--- a/lib/dns/Makefile.in
+++ b/lib/dns/Makefile.in
@@ -219,7 +219,7 @@ ${OBJS}: include
 dnstap.@O@: dnstap.c dnstap.pb-c.c
 
 dnstap.pb-c.c dnstap.pb-c.h include/dns/dnstap.pb-c.h: dnstap.proto
-       $(PROTOC_C) --c_out=. dnstap.proto
+       $(PROTOC_C) --c_out=. --proto_path ${srcdir} dnstap.proto
        cp -f dnstap.pb-c.h include/dns
 
 dnstap.pb-c.@O@: dnstap.pb-c.c