Remove CodeGenOptLevel::Other

Also introduced in #35174, and immediately unused.

Author: Mark-Simulacrum

src/librustc_codegen_llvm/back/write.rs

@@ -975,7 +975,6 @@ pub unsafe fn with_llvm_pmb(
         (llvm::CodeGenOptLevel::Default, ..) => {
             llvm::LLVMPassManagerBuilderUseInlinerWithThreshold(builder, 225);
         }
-        (llvm::CodeGenOptLevel::Other, ..) => bug!("CodeGenOptLevel::Other selected"),
     }
 
     f(builder);

src/librustc_codegen_llvm/llvm/ffi.rs

@@ -401,9 +401,6 @@ impl AsmDialect {
 #[derive(Copy, Clone, PartialEq)]
 #[repr(C)]
 pub enum CodeGenOptLevel {
-    // FIXME: figure out if this variant is needed at all.
-    #[allow(dead_code)]
-    Other,
     None,
     Less,
     Default,

src/rustllvm/PassWrapper.cpp

@@ -311,7 +311,6 @@ static Optional<CodeModel::Model> fromRust(LLVMRustCodeModel Model) {
 }
 
 enum class LLVMRustCodeGenOptLevel {
-  Other,
   None,
   Less,
   Default,