default or selected kernelversion does not have config value CONFIG_R8712_TX_AGGR.
Result is shown for kernelversion 6.9.9

Realtek RTL8712U Transmit Aggregation code

configname: CONFIG_R8712_TX_AGGR

Linux Kernel Configuration
└─>Device Drivers
└─>Staging drivers
└─>Realtek RTL8712U Transmit Aggregation code
In linux kernel since version 3.1 (release Date: 2011-10-24)  
This option provides transmit aggregation for the Realtek
RTL8712 USB device.

depends
CONFIG_BROKEN
CONFIG_R8712U
CONFIG_STAGING