patch 9.1.0628: MinGW: coverage files are not cleaned up

Problem:  MinGW: coverage files are not cleaned up
Solution: Adjust clean rule to remove the coverage files
          (Ken Takata)

closes: #15361

Signed-off-by: Ken Takata <kentkt@csc.jp>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/Make_cyg_ming.mak b/src/Make_cyg_ming.mak
index 5fb3a41..f082c96 100644
--- a/src/Make_cyg_ming.mak
+++ b/src/Make_cyg_ming.mak
@@ -1188,10 +1188,13 @@
 
 clean:
 	-$(DEL) $(OUTDIR)$(DIRSLASH)*.o
+	-$(DEL) $(OUTDIR)$(DIRSLASH)*.gcno
+	-$(DEL) $(OUTDIR)$(DIRSLASH)*.gcda
 	-$(DEL) $(OUTDIR)$(DIRSLASH)*.res
 	-$(DEL) $(OUTDIR)$(DIRSLASH)pathdef.c
 	-rmdir $(OUTDIR)
 	-$(DEL) $(MAIN_TARGET) vimrun.exe install.exe uninstall.exe
+	-$(DEL) *.gcno *.gcda
 	-$(DEL) *.map
 ifdef PERL
 	-$(DEL) if_perl.c