[FIR2IR] KT-57211: Support unsigned arrayOf-s in fir2ir

^KT-57211 Fixed

Merge-request: KT-MR-9294
Merged-by: Nikolay Lunyak <Nikolay.Lunyak@jetbrains.com>

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/IrBuiltIns.kt

@@ -115,6 +115,7 @@ abstract class IrBuiltIns {
     abstract val primitiveArrayForType: Map<IrType?, IrClassSymbol>
 
     abstract val unsignedTypesToUnsignedArrays: Map<UnsignedType, IrClassSymbol>
+    abstract val unsignedArraysElementTypes: Map<IrClassSymbol, IrType?>
 
     abstract val lessFunByOperandType: Map<IrClassifierSymbol, IrSimpleFunctionSymbol>
     abstract val lessOrEqualFunByOperandType: Map<IrClassifierSymbol, IrSimpleFunctionSymbol>

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/types/IrTypeUtils.kt

@@ -67,6 +67,7 @@ fun IrType.getArrayElementType(irBuiltIns: IrBuiltIns): IrType =
     } else {
         val classifier = this.classOrNull!!
         irBuiltIns.primitiveArrayElementTypes[classifier]
+            ?: irBuiltIns.unsignedArraysElementTypes[classifier]
             ?: throw AssertionError("Primitive array expected: $classifier")
     }