JVM IR: do not mangle property accessors of unsigned types in annotations

Before this change, we incorrectly mangled the names of annotation
methods (e.g. `getI-pVg5ArA` instead of `i`) because the isSpecial
condition was false.

compiler/testData/codegen/bytecodeListing/annotations/unsignedTypes.kt

@@ -0,0 +1,8 @@
+// WITH_RUNTIME
+
+annotation class Anno(
+    val b: UByte,
+    val i: UInt,
+    val l: ULong,
+    val s: UShort,
+)

compiler/testData/codegen/bytecodeListing/annotations/unsignedTypes.txt

@@ -0,0 +1,9 @@
+@java.lang.annotation.Retention
+@kotlin.Metadata
+public annotation class Anno {
+    // source: 'unsignedTypes.kt'
+    public abstract method b(): byte
+    public abstract method i(): int
+    public abstract method l(): long
+    public abstract method s(): short
+}