patch 8.0.0144: when using MSVC the GvimExt directory is cleaned twice

Problem:    When using MSVC the GvimExt directory is cleaned twice.
Solution:   Remove the lines. (Ken Takata)

Author: brammool

src/Make_mvc.mak

@@ -1123,9 +1123,6 @@ clean:
 	cd GvimExt
 	$(MAKE) /NOLOGO -f Makefile clean
 	cd ..
-	cd GvimExt
-	$(MAKE) /NOLOGO -f Makefile clean
-	cd ..
 	- if exist testdir\*.out del testdir\*.out
 
 test:

src/version.c

@@ -764,6 +764,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    144,
 /**/
     143,
 /**/