Revert "[FIR] Do not smartcast class delegation implemented properties"

This reverts commit bb6f466162.

Reverting the fix for KT-57417 as it causes failures in IntelliJ and
Space projects. May reintroduce fix after failures are investigated and
resolved.

compiler/testData/diagnostics/tests/smartCasts/varnotnull/classDelegation.fir.kt

@@ -1,11 +0,0 @@
-// ISSUE: KT-57417
-
-interface HasProperty {
-    val property: Int?
-}
-
-class Test(delegate: HasProperty) : HasProperty by delegate
-
-fun test(a: Test) {
-    if (a.property != null) <!SMARTCAST_IMPOSSIBLE!>a.property<!> + 1
-}

compiler/testData/diagnostics/tests/smartCasts/varnotnull/classDelegation.kt

@@ -1,11 +0,0 @@
-// ISSUE: KT-57417
-
-interface HasProperty {
-    val property: Int?
-}
-
-class Test(delegate: HasProperty) : HasProperty by delegate
-
-fun test(a: Test) {
-    if (a.property != null) <!DEBUG_INFO_SMARTCAST!>a.property<!> + 1
-}