`suboptimal_flops` incorrectly claims that `mul_add` is always more efficient

### Summary The documentation for [`mul_add`](https://doc.rust-lang.org/std/primitive.f64.html#method.mul_add) states: > Using `mul_add` may be more performant than an unfused multiply-add if the target architecture has a dedicated `fma` CPU instruction. However, this is not always true, and will be heavily dependant on designing algorithms with specific target hardware in mind. However, the lint message from `suboptimal_flops` says “multiply and add expressions can be calculated more efficiently and accurately”. The “more efficiently” part should not be stated without caveat. ### Reproducer Code: ```rust #![warn(clippy::suboptimal_flops)] fn foo(x: f64) -> f64 { x * 2.0 + 10.0 } ``` Current output: ``` warning: multiply and add expressions can be calculated more efficiently and accurately --> src/lib.rs:4:5 | 4 | x * 2.0 + 10.0 | ^^^^^^^^^^^^^^ help: consider using: `x.mul_add(2.0, 10.0)` ``` Desired output: ``` warning: multiply and add expressions can be calculated more accurately --> src/lib.rs:4:5 | 4 | x * 2.0 + 10.0 | ^^^^^^^^^^^^^^ help: consider using: `x.mul_add(2.0, 10.0)` ``` ### Version ```text rustc 1.96.0 (ac68faa20 2026-05-25) binary: rustc commit-hash: ac68faa20c58cbccd01ee7208bf3b6e93a7d7f96 commit-date: 2026-05-25 host: aarch64-apple-darwin release: 1.96.0 LLVM version: 22.1.2 ``` ### Additional Labels _No response_