%%JAVA_HOME%% replacement

From: Einar_Bjarni_Halldórsson <einar_at_isnic.is>
Date: Tue, 03 Jan 2023 10:27:50 UTC

I'm working on a patch for graylog, to allow setting graylog_java_home. 
I copied lines from the opensearch13 port, but %%JAVA_HOME%% in rc 
script isn't being replaced when I make && make install.

Anybody know why that is? I guess I'm missing something from the 
Makefile, but looking at opensearch13 Makefile, I can't figure out 
what's missing.