[FE 1.0] Support suspend only SAM conversions

^KT-50477 Fixed

compiler/testData/diagnostics/tests/samConversions/kt50477.fir.kt

@@ -0,0 +1,23 @@
+// !LANGUAGE: -SuspendOnlySamConversions
+
+fun interface FI {
+    suspend fun call() // suspending now(!!!)
+}
+
+fun accept(fi: FI): Int = TODO()
+
+suspend fun foo() {}
+fun foo2() {}
+
+fun main() {
+    val fi: suspend () -> Unit = {} // Lambda of a suspending(!!!) functional type
+    accept(fi) // ERROR: Type mismatch. Required: FI Found: suspend () → Unit
+
+    accept(::foo)
+    val x1 = ::foo
+    accept(x1) // ERROR: Type mismatch. Required: FI Found: suspend () → Unit
+
+    accept(::foo2)
+    val x2 = ::foo2
+    accept(x2)
+}

compiler/testData/diagnostics/tests/samConversions/kt50477.kt

@@ -0,0 +1,23 @@
+// !LANGUAGE: -SuspendOnlySamConversions
+
+fun interface FI {
+    suspend fun call() // suspending now(!!!)
+}
+
+fun accept(fi: FI): Int = TODO()
+
+suspend fun foo() {}
+fun foo2() {}
+
+fun main() {
+    val fi: suspend () -> Unit = {} // Lambda of a suspending(!!!) functional type
+    accept(<!TYPE_MISMATCH!>fi<!>) // ERROR: Type mismatch. Required: FI Found: suspend () → Unit
+
+    accept(::foo)
+    val x1 = ::foo
+    accept(<!TYPE_MISMATCH!>x1<!>) // ERROR: Type mismatch. Required: FI Found: suspend () → Unit
+
+    accept(::foo2)
+    val x2 = ::foo2
+    accept(x2)
+}

compiler/testData/diagnostics/tests/samConversions/kt50477.txt

@@ -0,0 +1,13 @@
+package
+
+public fun accept(/*0*/ fi: FI): kotlin.Int
+public suspend fun foo(): kotlin.Unit
+public fun foo2(): kotlin.Unit
+public fun main(): kotlin.Unit
+
+public fun interface FI {
+    public abstract suspend fun call(): kotlin.Unit
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}