Makefile: update default compatdir (#132)

This was broken in c41a762.

Author: elyscape

Makefile.am

@@ -25,7 +25,7 @@ EXTRA_DIST = CHANGES $(pkgdata_DATA) bash_completion.sh.in .dir-locals.el \
 
 install-data-hook:
 	tmpfile=`mktemp $${TMPDIR:-/tmp}/bash_completion.XXXXXX` && \
-	sed -e 's|=/etc/bash_completion\.d|=$(compatdir)|' \
+	sed -e 's|-/etc/bash_completion\.d|-$(compatdir)|' \
 	    $(DESTDIR)$(pkgdatadir)/bash_completion > $$tmpfile && \
 	cat $$tmpfile > $(DESTDIR)$(pkgdatadir)/bash_completion && \
 	sed -e 's|\$${prefix}|$(prefix)|' \