patch 8.2.3620: memory leak reported in libtlib

Problem:    Memory leak reported in libtlib.
Solution:   Call del_curterm() when cleaning up memory.  Rename term.h to
            termdefs.h to avoid a name clash.
diff --git a/src/Make_cyg_ming.mak b/src/Make_cyg_ming.mak
index 1b881b5..fe04cb5 100644
--- a/src/Make_cyg_ming.mak
+++ b/src/Make_cyg_ming.mak
@@ -1140,7 +1140,7 @@
 ###########################################################################
 INCL =	vim.h alloc.h ascii.h ex_cmds.h feature.h errors.h globals.h \
 	keymap.h macros.h option.h os_dos.h os_win32.h proto.h regexp.h \
-	spell.h structs.h term.h beval.h $(NBDEBUG_INCL)
+	spell.h structs.h termdefs.h beval.h $(NBDEBUG_INCL)
 GUI_INCL = gui.h
 ifeq ($(DIRECTX),yes)
 GUI_INCL += gui_dwrite.h