PVS-Studio warning V583 for MAME

unsigned Dasm9900 (char *buffer, unsigned pc, int model_id,
                   const UINT8 *oprom, const UINT8 *opram)
{
  ...
  buffer += sprintf(buffer,
    bit_position ? ",(%d," : ",(%d,", bit_position);
  ...
}

This suspicious code was found in MAME project by PVS-Studio static code analyzer.
Warning message is:
V583 The '?:' operator, regardless of its conditional expression, always returns one and the same value: ",(%d,".  9900dasm.c 670

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