We have adjusted the registration method for MTD devices
in nuttx/boards, replacing the previous approach using
ftl_initialize() and bchdev_register() with
register_mtddriver().
When registering MTD devices via register_mtddriver(),
FTL and BCH wrappers will be added during the open() process:
1. Character Device Mode:
When accessing the MTD device node via the open() interface,
the device will be automatically converted to a character
device. Both FTL and BCH wrappers will be implicitly added,
provided that BCH support is enabled in the configuration.
2. Block Device Mode:
When accessing the MTD device node via open_blockdriver(),
the device will be treated as a block device, with only
the FTL wrapper automatically applied.
Due to the automatic wrapping of MTD devices during the
open() process, the legacy registration methods
ftl_initialize() and bchdev_register() are no longer
required for MTD device registration for user code and should
be used only internally within fs and driver code.
Signed-off-by: jingfei <jingfei@xiaomi.com>