Fix MinGW toolchain detection

Updated the comment in change I6bef2ab5, but missed adding the code to
the commit.

Change-Id: I14d300489b79730e3995175bfe5f9271b569abe3

build/make/configure.sh

@@ -519,7 +519,7 @@ process_common_toolchain() {
                 tgt_isa=universal
                 tgt_os=darwin9
                 ;;
-            *msys*|*cygwin*)
+            *mingw32*|*cygwin*)
                 tgt_os=win32
                 ;;
             *linux*|*bsd*)