Suspend call detector: fix delegated properties checking

compiler/testData/diagnostics/testsWithStdLib/coroutines/illegalSuspendCallsForDelegated.kt

@@ -0,0 +1,8 @@
+fun bar(d: Delegate): String {
+    val x: String by <!ILLEGAL_SUSPEND_FUNCTION_CALL!>d<!>
+    return x
+}
+
+class Delegate {
+    suspend operator fun getValue(thisRef: Any?, property: Any?): String = ""
+}

compiler/testData/diagnostics/testsWithStdLib/coroutines/illegalSuspendCallsForDelegated.txt

@@ -0,0 +1,11 @@
+package
+
+public fun bar(/*0*/ d: Delegate): kotlin.String
+
+public final class Delegate {
+    public constructor Delegate()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public final operator suspend fun getValue(/*0*/ thisRef: kotlin.Any?, /*1*/ property: kotlin.Any?): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}