Update code signing command for DMG target.

Author: michaelrsweet

Makefile.in

@@ -82,7 +82,7 @@ VERSION	=	@SVERSION@
 
 dmg:
 echo Signing HTMLDOC application bundle
-codesign -s "$(CODESIGN_IDENTITY)" --timestamp -o runtime htmldoc/htmldoc.app
+codesign -f -s "$(CODESIGN_IDENTITY)" --timestamp -o runtime htmldoc/htmldoc.app
 echo Creating archive for notarization
 rm -f htmldoc/htmldoc.zip
 ditto -c -k --keepParent htmldoc/htmldoc.app htmldoc/htmldoc.zip