Provide 'datarootdir' parameter to shutup configuration warning,

'packages/EPM/curl.list.in seems to ignore the --datarootdir setting'

packages/EPM/curl.list.in

@@ -8,6 +8,7 @@ $mandir=@mandir@
 $libdir=@libdir@
 $srcdir=@top_srcdir@
 $includedir=@includedir@
+$datarootdir=@datarootdir@
 
 # Product information
 %product curl