Previously, renaming a VLAN or deleting and recreating it with a
different name did not update the displayed name. The vlan_names[]
array is an append-only buffer where vlan_name() returns the first
matching entry, so stale entries kept winning.
This commit adds vlan_name_remove(), which locates an entry by
VLAN ID and removes it via array compaction. The function is called
in two places:
- parse_vlan() in cmd_parser.c, before appending a new name entry,
to remove any pre-existing entry for the same VLAN ID
- vlan_delete() in rtl837x_port.c, to clean up the name when a
VLAN is removed
The implementation reuses the existing vlan_name() lookup, scans for
the trailing space of the matched entry, then shifts remaining bytes
left. Locals are declared as static __xdata to avoid the SDCC
overlay segment limit on banked functions.
Tested on KeepLiNK KP-9000-6XH-X:
- vlan 99 AAA p1u; vlan 99 BBB -> name updated to BBB
- vlan 99 d; vlan 99 CCC p1u -> name correctly CCC, not stale AAA
Note: This fix addresses the runtime XMEM state. Persistence of
renamed VLAN names across reboot requires the user to download and
re-upload /config, as is the existing pattern for all configuration
changes in this firmware.