graphics/gocr: Remove MOTDCL_BIN and MODTK_BIN from SUBST_VARS.

Add MODTK_BIN to SUBST_VARS; no longer added by the Tk port module.



diff -Nurp /usr/ports//graphics/gocr/Makefile ./Makefile
--- /usr/ports//graphics/gocr/Makefile Thu Oct 5 10:49:27 2023
+++ ./Makefile Sat Feb 7 10:11:16 2026
@@ -23,6 +23,7 @@ CONFIGURE_STYLE=gnu
CONFIGURE_ARGS= --with-netpbm=${PREFIX}
USE_GMAKE= Yes
FAKE_FLAGS+= prefix=${PREFIX} exec_prefix=${PREFIX}
+SUBST_VARS= MODTK_BIN

MULTI_PACKAGES= -main -gui