patch 8.1.1662: cannot build uninstal.exe with some version of MinGW

Problem:    Cannot build uninstal.exe with some version of MinGW.
Solution:   Add -lole32. (Rene Nyffenegger, closes #4646)
diff --git a/src/Make_cyg_ming.mak b/src/Make_cyg_ming.mak
index 1e1b243..d0769c3 100644
--- a/src/Make_cyg_ming.mak
+++ b/src/Make_cyg_ming.mak
@@ -1006,7 +1006,7 @@
 	$(CC) $(CFLAGS) -o install.exe dosinst.c $(LIB) -lole32 -luuid
 
 uninstal.exe: uninstal.c
-	$(CC) $(CFLAGS) -o uninstal.exe uninstal.c $(LIB)
+	$(CC) $(CFLAGS) -o uninstal.exe uninstal.c $(LIB) -lole32
 
 ifeq ($(VIMDLL),yes)
 $(TARGET): $(OUTDIR) $(OBJ)