[Plugin] Enable fusilli plugin build in TheRock

[AaronStGeorge]

Fusilli plugin build is available in TheRock, but disabled. The build should be enabled once:

1. multi-arch support lands
2. hipDNN gets some breaking changes through (this is done as far as I know).
3. libIREECompiler.so is building as part of TheRock (with its own LLVM) and fusilli plugin uses that build correctly

NOTE: libIREECompiler.so should eventually use the standard AMD LLVM that's already part of TheRock. The current plan of record is to release before that. There are three levels of IREE <> TheRock integration

1. Side-load compiler (either iree-compile or libIREECompiler.so from a prebuilt nightly)
2. Build libIREECompiler.so from source against IREE's LLVM
3. Build libIREECompiler.so from source against AMD's LLVM

Currently we are at 1, the plan is to release as part of TheRock at 2, and work towards a longer term goal of 3.

[AaronStGeorge]

This work entails both landing IREE in TheRock (PR: ROCm/TheRock#3264) as well as enabling the build in the multi stage pipeline (issue: ROCm/TheRock#3451), these will be separate PRs

[AaronStGeorge]

ROCm/TheRock#3611