metalink: build fixes and adjustments II

Additionally, make hash checking ability mandatory in order to allow metalink
support in curl.

A command line option could be introduced to skip hash checking at runtime,
but the ability to check hashes should always be built-in when providing
metalink support.

src/tool_getparam.c

@@ -39,11 +39,11 @@
 #include "tool_help.h"
 #include "tool_helpers.h"
 #include "tool_libinfo.h"
+#include "tool_metalink.h"
 #include "tool_msgs.h"
 #include "tool_paramhlp.h"
 #include "tool_parsecfg.h"
 #include "tool_version.h"
-#include "tool_metalink.h"
 
 #include "memdebug.h" /* keep this as LAST include */