I've used different PC Engines device (ALIX 2D2) for years and both temperature monitoring (via lm-sensors) and LEDs worked fine. Unfortunately, on quite similar but older WRAP 2C I'm not able to use neither lm-sensors (no sensors are detected by sensors-detect) nor LEDs (no settings in LuCI). Are those two things possible on WRAP?
OpenWrt version used: 19.07.8 x86
Normally, I'd suggest to try a full-featured general purpose linux distribution to check what
lm-sensors detects on that, while running a full-featured kernel. Given the 80i486 hardware that's not going to be an option here, though. I wonder how relevant temperature readings are on this SOC to begin with.
That leaves you with searching the web for hints, checking PCI IDs and DMI strings against the kernel source, to check for options.
Geode SC1100 supports temperature readouts just about the same way it works for much newer LX-series (used in ALIX). Theoretically when kmod-hwmon-w83627hf, kmod-hwmod-lm77, lm-sensors, lm-sensors-detect and their dependencies are installed everything should simply start working but that first module fails to even load.