doc: group file system/storage APIs

Group NVS, Filesystems and Settings under "File System and Storage" in
doxygen.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>

include/fs.h

@@ -47,8 +47,8 @@ enum fs_type {
 };
 
 /**
- * @brief File System
- * @defgroup file_system File System
+ * @brief File System and Storage
+ * @defgroup file_system_storage File System and Storage
  * @{
  * @}
  */
@@ -56,7 +56,7 @@ enum fs_type {
 /**
  * @brief File System Data Structures
  * @defgroup data_structures File System Data Structures
- * @ingroup file_system
+ * @ingroup file_system_storage
  * @{
  */
 
@@ -185,7 +185,7 @@ struct fs_file_system_t {
 /**
  * @brief File System APIs
  * @defgroup file_system_api File System APIs
- * @ingroup file_system
+ * @ingroup file_system_storage
  * @{
  */
 

include/nvs/nvs.h

@@ -15,6 +15,7 @@ extern "C" {
 /**
  * @brief Non-volatile Storage
  * @defgroup nvs Non-volatile Storage
+ * @ingroup file_system_storage
  * @{
  * @}
  */

include/settings/settings.h

@@ -18,6 +18,7 @@ extern "C" {
 
 /**
  * @defgroup settings Settings subsystem
+ * @ingroup file_system_storage
  * @{
  */