net/slip: Change SLIP to use IOB

[wengzhe]

Summary

SLIP seems to be broken after IOB offload (#8239), try to fix it.

Impact

Change SLIP device to use IOB

Testing

No actual boards for testing, may need your help to confirm whether it works.

[xiaoxiang781216]

@michi-jung could you help us verify this patch?

[michi-jung]

@michi-jung could you help us verify this patch?

Hi @xiaoxiang781216 and @wengzhe. Yes, patch is working fine for me. Thanks!

Could you please increase the buffer array in slip_initialize to 12 characters to silence compiler warnings about potentially truncated output (INT_MIN requires 11 chars + NUL)? Thanks!

[wengzhe]

@michi-jung could you help us verify this patch?

Hi @xiaoxiang781216 and @wengzhe. Yes, patch is working fine for me. Thanks!

Could you please increase the buffer array in slip_initialize to 12 characters to silence compiler warnings about potentially truncated output (INT_MIN requires 11 chars + NUL)? Thanks!

@michi-jung Updated, it this what you need?

[michi-jung]

@michi-jung could you help us verify this patch?

Hi @xiaoxiang781216 and @wengzhe. Yes, patch is working fine for me. Thanks!
Could you please increase the buffer array in slip_initialize to 12 characters to silence compiler warnings about potentially truncated output (INT_MIN requires 11 chars + NUL)? Thanks!

@michi-jung Updated, it this what you need?

@wengzhe Yes, exactly. Thanks!