Improve support of custom equals in inline classes

- Ensure that typed equals parameter's type is a star projection of
  corresponding inline class

- Make possible to declare typed equals that returns 'Nothing'

- Forbid type parameters in typed equals operator declaration

^KT-54909 fixed
^KT-54910 fixed

compiler/testData/codegen/box/inlineClasses/inlineClassEqualsOverridenForCollections.kt

@@ -7,7 +7,7 @@ import kotlin.math.abs
 
 OPTIONAL_JVM_INLINE_ANNOTATION
 value class IC(val x: Double) {
-    fun equals(other: IC): Boolean {
+    operator fun equals(other: IC): Boolean {
         return abs(x - other.x) < 0.1
     }