Remove unused PRELOADENV macro in ruby-runner.h

template/ruby-runner.h.in

@@ -1,7 +1,6 @@
 #define ABS_SRCDIR "@abs_srcdir@"
 #define BUILDDIR   "@abs_top_builddir@"
 #define LIBPATHENV "@LIBPATHENV@"
-#define PRELOADENV "@PRELOADENV@"
 #define PATH_SEPARATOR "@PATH_SEPARATOR@"
 #define PATH_SEP   '@PATH_SEPARATOR@'
 #define EXTOUT     "@EXTOUT@"