Rollup merge of #161257 - TimNN:no-minicore, r=RalfJung

Ignore target feature test when LLVM fails to compile minicore

https://github.com/llvm/llvm-project/pull/111334 made LLVM reject certain target feature + ABI mismatches (ARM hard / soft float) which means that minicore now [fails to build](https://buildkite.com/llvm-project/rust-llvm-integrate-prototype/builds/48076/canvas?sid=01a00f60-fa22-4f35-a854-0b6d1c302123) with errors like `error: <unknown>:0:0: in function _RNvXsc_Cs4Af2OiBEA1T_8minicoreiNtB5_3Add3add i32 (i32, i32): calling convention is hard-float, but floating-point registers are unavailable`

This PR ignores the test where this currently happens on LLVM 24, assuming that if LLVM is now rejecting this, we should turn the rust-side warning into an error as well. Created https://github.com/rust-lang/rust/issues/161276 to track that.

r? @RalfJung (since you worked ~recently on these, including migrating them to minicore)

@rustbot label llvm-main