revert kconfig of pthread

components/libc/Kconfig

@@ -76,16 +76,16 @@ if RT_USING_POSIX
     config RT_USING_POSIX_AIO
         bool "Enable AIO"
         default n
+endif
 
-    config RT_USING_PTHREADS
-        bool "Enable pthreads APIs"
-        default n
+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_PTHREADS
+    config PTHREAD_NUM_MAX
+        int "Maximum number of pthreads"
+        default 8
 endif
 
 endmenu