net: nfc: nci: Fix zero-length proprietary notifications

net: nfc: nci: Fix zero-length proprietary notifications

NCI NFC controllers may have proprietary OIDs with zero-length payload.
One example is: drivers/nfc/nxp-nci/core.c, NXP_NCI_RF_TXLDO_ERROR_NTF.

Allow a zero length payload in proprietary notifications *only*.

Before:

-- >8 --
kernel: nci: nci_recv_frame: len 3
-- >8 --

After:

-- >8 --
kernel: nci: nci_recv_frame: len 3
kernel: nci: nci_ntf_packet: NCI RX: MT=ntf, PBF=0, GID=0x1, OID=0x23, plen=0
kernel: nci: nci_ntf_packet: unknown ntf opcode 0x123
kernel: nfc nfc0: NFC: RF transmitter couldn't start. Bad power and/or configuration?
-- >8 --

After fixing the hardware:

-- >8 --
kernel: nci: nci_recv_frame: len 27
kernel: nci: nci_ntf_packet: NCI RX: MT=ntf, PBF=0, GID=0x1, OID=0x5, plen=24
kernel: nci: nci_rf_intf_activated_ntf_packet: rf_discovery_id 1
-- >8 --

Fixes: d24b03535e5e ("nfc: nci: Fix uninit-value in nci_dev_up and nci_ntf_packet")
Signed-off-by: Ian Ray <ian.ray@gehealthcare.com>
Link: https://patch.msgid.link/20260302163238.140576-1-ian.ray@gehealthcare.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>