Fix the MS-DOS build broken by recent leim-related changes.

 msdos/sedleim.inp (RUN_EMACS): Replace BUILT_EMACS with EMACS.
 Remove stale editing of "else make quail".
 (.PHONY, compile-targets): Remove targets.
 (compile-main): Edit into something that can be done without
 requiring a Unixy shell.
 (bootstrap-clean): Likewise: edit to not require $(setwins).
 msdos/sed1v2.inp: Edit "cd $(leimdir) && $(MAKE) ..." into the
 equivalent "$(MAKE) $(MFLAGS) -C $(leimdir) ..." command.