[posix]将pthread收缩到posix选项之下，将选定DFS后由DFS选定POSIX 改为选择posix后选择dfs

components/libc/Kconfig

@@ -10,7 +10,6 @@ if RT_USING_LIBC
 
     config RT_LIBC_USING_FILEIO
         bool "Enable libc with file operation, eg.fopen/fwrite/fread/getchar"
-        select RT_USING_DFS
         select RT_USING_POSIX
         default n
 
@@ -37,21 +36,11 @@ config RT_LIBC_DEFAULT_TIMEZONE
     range -12 12
     default 8
 
-config RT_USING_PTHREADS
-    bool "Enable pthreads APIs"
-    default n
-
-if RT_USING_PTHREADS
-    config PTHREAD_NUM_MAX
-        int "Maximum number of pthreads"
-        default 8
-endif
-
-if RT_USING_DFS
 config RT_USING_POSIX
-        bool "Enable POSIX layer, open/read/write/select etc"
+    bool "Enable basic POSIX layer, open/read/write/close etc"
+    select RT_USING_DFS
     select RT_USING_DFS_DEVFS
-        default y
+    default n
 
 if RT_USING_POSIX
     config RT_USING_POSIX_MMAP
@@ -69,8 +58,16 @@ if RT_USING_DFS
     config RT_USING_POSIX_AIO
         bool "Enable AIO"
         default n
-    endif
 
+    config RT_USING_PTHREADS
+        bool "Enable pthreads APIs"
+        default n
+
+    if RT_USING_PTHREADS
+        config PTHREAD_NUM_MAX
+            int "Maximum number of pthreads"
+            default 8
+    endif
 endif
 
 endmenu

components/net/Kconfig

@@ -41,9 +41,7 @@ config RT_USING_SAL
         config SAL_USING_POSIX
             bool "Enable BSD socket operated by file system API"
             default n
-            select RT_USING_DFS
-            select RT_USING_LIBC
-            select RT_USING_POSIX
+            select RT_LIBC_USING_FILEIO
             help
                 Let BSD socket operated by file system API, such as read/write and involveed in select/poll POSIX APIs.