Rename V23_PROFILE variable to JIRI_PROFILE.

Change-Id: I864ef1ecd82cd2d5005c944dc0d5f9abb63d2cf5
MultiPart: 4/7
diff --git a/extension/Makefile b/extension/Makefile
index 748dc06..081f593 100644
--- a/extension/Makefile
+++ b/extension/Makefile
@@ -17,7 +17,7 @@
 
 define COMPILE-NACL-PLUGIN
 	mkdir -p $(dir $2)
-	GOROOT= V23_PROFILE=nacl v23 go build -o $2 $1
+	GOROOT= JIRI_PROFILE=nacl v23 go build -o $2 $1
 endef
 
 all: vanadium.zip