default or selected kernelversion does not have config value CONFIG_ATM_IDT77252_DEBUG.
Result is shown for kernelversion 5.9.9

Enable debugging messages

configname: CONFIG_ATM_IDT77252_DEBUG

Linux Kernel Configuration
└─> Device Drivers
└─> Network device support
└─> ATM drivers
└─> Enable debugging messages

Somewhat useful debugging messages are available. The choice of
messages is controlled by a bitmap. This may be specified as a
module argument. See the file <file:drivers/atm/idt77252.h> for
the meanings of the bits in the mask.

When active, these messages can have a significant impact on the
speed of the driver, and the size of your syslog files! When
inactive, they will have only a modest impact on performance.