include the symbols-in-versions file in the release archive

docs/libcurl/Makefile.am

@@ -60,8 +60,8 @@ PDFPAGES = curl_easy_cleanup.pdf curl_easy_getinfo.pdf curl_easy_init.pdf \
 
 CLEANFILES = $(HTMLPAGES) $(PDFPAGES)
 
-EXTRA_DIST = $(man_MANS) $(HTMLPAGES) index.html $(PDFPAGES) libcurl.m4 ABI
-
+EXTRA_DIST = $(man_MANS) $(HTMLPAGES) index.html $(PDFPAGES) libcurl.m4 ABI \
+  symbols-in-versions
 MAN2HTML= roffit --mandir=. < $< >$@
 
 SUFFIXES = .3 .html