Make the canned config.h files used on Win32 more minimal

Make the canned config.h files used on Win32 more minimal

These are used in their unedited form to build miniperl, so should
represent a minimal configuration

The plan is to use miniperl's "-V" output in makedef.pl, so it is
important that it doesn't include any of the optional things in the
makefiles that the user might have chosen to disable

(The actual config.h used to build perl itself is, of course, an
edited version of these canned configs produced by using miniperl
to run config_h.PL so these changes won't affect perl itself)

p4raw-id: //depot/perl@25208