use the patch from the build-instructions;
# >>> patch al_hal_serdes.c <<<
wget -N https://raw.githubusercontent.com/masmbit/Netgear-R9000-Build/master/bin/01.09.2024/patch/al_hal_serdes.patch -P target/linux/alpine/files/arch/arm/mach-alpine/
patch -N target/linux/alpine/files/arch/arm/mach-alpine/al_hal_serdes.c target/linux/alpine/files/arch/arm/mach-alpine/al_hal_serdes.patch
# >>> patch al_init_eth_kr.c <<<
wget -N https://raw.githubusercontent.com/masmbit/Netgear-R9000-Build/master/bin/01.09.2024/patch/al_init_eth_kr.patch -P target/linux/alpine/files/drivers/net/ethernet/al/
patch -N target/linux/alpine/files/drivers/net/ethernet/al/al_init_eth_kr.c target/linux/alpine/files/drivers/net/ethernet/al/al_init_eth_kr.patch
# >>> patch freeswitch Makefile <<<
wget -N https://raw.githubusercontent.com/masmbit/Netgear-R9000-Build/master/bin/01.09.2024/patch/freeswitch.Makefile.patch -P package/feeds/telephony/freeswitch/
patch -N package/feeds/telephony/freeswitch/Makefile package/feeds/telephony/freeswitch/freeswitch.Makefile.patch