Fresh Git version - undefined reference to `vlan_find'

Code:

[code]ranlib bin/blib.a

ld  -m elf_i386 -N --no-check-sections --section-start=.prefix=0   --gc-sections -static -T arch/x86/scripts/pcbios.lds  -u _pcirom_start --defsym check__pcirom_start=_pcirom_start   -u obj_intel --defsym check_obj_intel=obj_intel   -u pci_devlist_8086100e --defsym check_pci_devlist_8086100e=pci_devlist_8086100e   -u obj_config --defsym check_obj_config=obj_config   -u obj_config_pcbios --defsym check_obj_config_pcbios=obj_config_pcbios  --defsym pci_vendor_id=0x8086 --defsym pci_device_id=0x100e -e _pcirom_start bin/version.82540em.rom.o bin/blib.a -o bin/82540em.rom.tmp \

        --defsym _build_id=`perl -e 'printf "0x%08x", int ( rand ( 0xffffffff ) );'` \

        --defsym _build_timestamp=1587336334 \

        -Map bin/82540em.rom.tmp.map

bin/blib.a(netdevice.o): In function `net_pull_tags':

/home/gateadmin/files/soft/pxe/ipxe/tmp/ipxe_1.0.0+git-20200420/src/net/netdevice.c:1072: undefined reference to `vlan_find'

Makefile.housekeeping:1191: recipe for target 'bin/82540em.rom.tmp' failed

make[2]: *** [bin/82540em.rom.tmp] Error 1

rm bin/version.82540em.rom.o

make[2]: Leaving directory '/home/gateadmin/files/soft/pxe/ipxe/tmp/ipxe_1.0.0+git-20200420/src'

dh_auto_build: cd src && make -j8 V=1 NO_WERROR=1 VERSION=1.0.0\+git-20190109.133f4c4-0ubuntu2-my bin/82540em.rom returned exit code 2

debian/rules:37: recipe for target 'src/bin/82540em.rom' failed

make[1]: *** [src/bin/82540em.rom] Error 2

make[1]: Leaving directory '/home/gateadmin/files/soft/pxe/ipxe/tmp/ipxe_1.0.0+git-20200420'

debian/rules:12: recipe for target 'build' failed

make: *** [build] Error 2

dpkg-buildpackage: error: debian/rules build subprocess returned exit status 2

Code:

/**

 * Identify VLAN device (when VLAN support is not present)

 *

 * @v trunk                    Trunk network device

 * @v tag                      VLAN tag

 * @ret netdev               VLAN device, if any

 */

__weak struct net_device * vlan_find ( struct net_device *trunk __unused,

                                                      unsigned int tag __unused ) {

            return NULL;

}