[drivers][serial] marshal RT_DEVICE_CTRL_CONFIG from userspace

Close the remaining userspace ioctl boundary gaps on top of the serial v1/v2
LWP marshaling:
- In serial_fops_ioctl() for both dev_serial.c and dev_serial_v2.c, return 0
  directly after updating fd->flags on F_SETFL instead of forwarding to
  ops->control(), and reject any unmarshaled/unknown command from an LWP
  caller with -RT_ENOSYS instead of passing raw user pointers into
  rt_device_control() / serial->ops->control().
- Guard the LWP marshaling block with defined(RT_USING_LWP) &&
  defined(ARCH_MM_MMU), matching lwp_user_mm.h.
- In rt_serial_control(), reject baudrate == 0 (e.g. B0 or unmapped speed)
  with -RT_EINVAL in TCSETA*/TCSETS* just like RT_DEVICE_CTRL_CONFIG, and
  add missing RT_NULL and ops->configure checks in v1/v2 control handlers.

Fixes #11429

0 files changed, 0 insertions, 0 deletions