default or selected kernelversion does not have config value CONFIG_LAN_SAA9730.
Result is shown for kernelversion 5.4.123

Philips SAA9730 Ethernet support (EXPERIMENTAL)

modulename: saa9730.ko

configname: CONFIG_LAN_SAA9730

Linux Kernel Configuration
└─>Networking support
└─>Ethernet (10 or 100Mbit)
└─>Philips SAA9730 Ethernet support (EXPERIMENTAL)
In linux kernel since version 2.6.12  
The SAA9730 is a combined multimedia and peripheral controller used
in thin clients, Internet access terminals, and diskless
workstations.
See <http://www.semiconductors.philips.com/pip/SAA9730_flyer_1>.

source code:
depends
CONFIG_EXPERIMENTAL
CONFIG_MIPS
CONFIG_NETDEVICES
CONFIG_NET_PCI
NOT CONFIG_UML