JVM_IR: remove a suspend-related hack from BridgeLowering

`invoke` in suspend lambdas overrides FunctionN.invoke, so the
refactored BridgeLowering already generates correct bridges there.
All the hack does is break overrides of interface suspend methods.

compiler/testData/codegen/box/coroutines/bridges/interfaceSpecialization.kt

@@ -0,0 +1,23 @@
+// IGNORE_BACKEND_FIR: JVM_IR
+// WITH_RUNTIME
+// WITH_COROUTINES
+// COMMON_COROUTINES_TEST
+
+import helpers.*
+import COROUTINES_PACKAGE.*
+
+interface I1<A, B> {
+    suspend fun f(a: A, b: B): String
+}
+
+class C<A> : I1<A, String> {
+    override suspend fun f(a: A, b: String): String = b
+}
+
+fun box(): String {
+    var result = "fail"
+    suspend {
+        result = (C<Unit>() as I1<Unit, String>).f(Unit, "OK")
+    }.startCoroutine(EmptyContinuation)
+    return result
+}