drivers/Kconfig: Add an option, CONFIG_DRVR_MKRD, to control whether or not the mkrd() implementation is build. Otherwise, if mkrd() is built unconditionally, it will be drawn into every build whether it is used or not and will increase the build size.

include/nuttx/drivers/ramdisk.h

@@ -122,7 +122,7 @@ int romdisk_register(int minor, FAR const uint8_t *buffer, uint32_t nsectors,
  *
  ****************************************************************************/
 
-#ifdef CONFIG_FS_WRITABLE
+#ifdef CONFIG_DRVR_MKRD
 int mkrd(int minor, uint32_t nsectors, uint16_t sectsize, uint8_t rdflags);
 #endif
 

include/sys/boardctl.h

@@ -99,7 +99,7 @@
  * CMD:           BOARDIOC_MKRD
  * DESCRIPTION:   Create a RAM disk
  * ARG:           Pointer to read-only instance of struct boardioc_mkrd_s.
- * CONFIGURATION: CONFIG_FS_WRITABLE
+ * CONFIGURATION: CONFIG_DRVR_MKRD
  * DEPENDENCIES:  None
  *
  * CMD:           BOARDIOC_APP_SYMTAB
@@ -213,7 +213,7 @@
 
 /* Structures used with IOCTL commands */
 
-#ifdef CONFIG_FS_WRITABLE
+#ifdef CONFIG_DRVR_MKRD
 /* Describes the RAM disk to be created */
 
 struct boardioc_mkrd_s