default or selected kernelversion does not have config value CONFIG_USB_MUSB_AM335X_CHILD.
Result is shown for kernelversion 6.9.9

CONFIG_USB_MUSB_AM335X_CHILD (not configurable)

modulename: musb_am335x.ko

configname: CONFIG_USB_MUSB_AM335X_CHILD

Linux Kernel Configuration
└─>Device Drivers
└─>USB support
└─>USB_MUSB_AM335X_CHILD
In linux kernel since version 3.10 (release Date: 2013-06-30)  
source code:
drivers/usb/musb/musb_am335x.c