Free memory after use

Change-Id: I2c60ba7b84e0a45a2be51c9d748e2d030c16487c
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@nokia.com>

src/libs/utils/process_stub_win.c

@@ -221,6 +221,7 @@ int main()
         systemError("Wait for debugee failed, error %d\n");
     CloseHandle(pi.hProcess);
     CloseHandle(pi.hThread);
+    free(env);
     doExit(0);
     return 0;
 }