Usual patch to produce Linux-like .so files on FreeBSD

--- a/build/ltmain.sh	2023-02-24 11:51:18.000000000 +0900
+++ b/build/ltmain.sh	2024-01-06 13:46:15.460224000 +0900
@@ -9107,9 +9107,9 @@
 	    revision=$number_revision
 	    ;;
 	  freebsd-aout|qnx|sunos)
-	    current=$number_major
-	    revision=$number_minor
-	    age=0
+	    current=`expr $number_major + $number_minor`
+	    age=$number_minor
+	    revision=$number_revision
 	    ;;
 	  irix|nonstopux)
 	    func_arith $number_major + $number_minor
