Sync with maint

* maint:
  mingw: allow building with an MSYS2 runtime v3.x

Author: gitster

config.mak.uname

@@ -568,7 +568,7 @@ ifneq (,$(wildcard ../THIS_IS_MSYSGIT))
 	NO_GETTEXT = YesPlease
 	COMPAT_CLFAGS += -D__USE_MINGW_ACCESS
 else
-	ifeq ($(shell expr "$(uname_R)" : '2\.'),2)
+	ifneq ($(shell expr "$(uname_R)" : '1\.'),2)
 		# MSys2
 		prefix = /usr/
 		ifeq (MINGW32,$(MSYSTEM))