Added TCA9539 like in AFCZ. I reduced enable lines to 18 to avoid second IO expander. Consequences:
AMS_CLK_VCC3V3 LDO enable connected to VIN (P3V5).
P2V5 / DAC_AVTT enable connected to VIN (P5V0).
One common enable signal for DAC_AVCC / DAC_AVCCAUX / ADC_AVCC (Xilinx DS926: can be powered at any time and have no power-up sequencing requirements.)
As in AFC and AFCZ, add MCP23016 for power sequecing.