[dfs] 将文件系统默认最大数量以及最大类型改为4

components/dfs/Kconfig

@@ -14,13 +14,11 @@ if RT_USING_DFS
 
     config DFS_FILESYSTEMS_MAX
         int "The maximal number of mounted file system"
-        default 4 if RT_USING_DFS_NFS
-        default 2
+        default 4
 
     config DFS_FILESYSTEM_TYPES_MAX
         int "The maximal number of file system type"
-        default 4 if RT_USING_DFS_NFS
-        default 2
+        default 4
 
     config DFS_FD_MAX
         int "The maximal number of opened files"