Fix EPSOFF check logic in D3D physics method

[yumouwei]

From communications with Jayson Barr and Kurt Holtrop:

I remember that a while back we made the switch in epsoff signal to be high=good and 0=bad. How can we figure out what day / shot that changed?
...
The wiring was changed during the 2023/2024 vent so between the last plasma shot of 2023 and the first power supply test shot of 2024.
The last plasma shot on 6/29/23 was 196645. (pre-change)
The first low power supply test shot of 2024 was 198183 on 4/24/24. (post-change)

Affected physics methods:

• get_ip_parameters
• get_rt_ip_parameters