Change FUNCTION_EXPRESSION_WITH_NAME severity to ERROR

Also drop deprecation related parts and get rid of usages of this `feature` within testData

compiler/testData/codegen/boxInline/functionExpression/extension.1.kt

@@ -1,6 +1,6 @@
 fun test1(): Int {
     val inlineX = Inline(9)
-    return inlineX.calcExt(fun smth(z: Int) = z, 25)
+    return inlineX.calcExt(fun(z: Int) = z, 25)
 }
 
 fun test2(): Int {

compiler/testData/codegen/boxInline/nonLocalReturns/returnFromFunctionExpr.1.kt

@@ -9,15 +9,10 @@ fun test2(): String = (l@ fun (): String {
     return "fail"
 }) ()
 
-fun test3(): String = (l@ fun bar(): String {
-    foo { return@bar "OK" }
-    return "fail"
-}) ()
-
 fun box(): String {
     if (test() != "OK") return "fail 1: ${test()}"
 
     if (test2() != "OK") return "fail 2: ${test2()}"
 
-    return test3()
+    return "OK"
 }

compiler/testData/codegen/boxInline/nonLocalReturns/simpleFunctional.1.kt

@@ -21,7 +21,7 @@ fun test1(local: Int, nonLocal: String, doNonLocal: Boolean): String {
 fun test2(local: Int, nonLocal: String, doNonLocal: Boolean): String {
 
     val localResult = doCall(
-            fun xxx(): Int {
+            xxx@ fun(): Int {
                 if (doNonLocal) {
                     return@test2 nonLocal
                 }
@@ -39,7 +39,7 @@ fun test2(local: Int, nonLocal: String, doNonLocal: Boolean): String {
 fun test3(local: Int, nonLocal: String, doNonLocal: Boolean): String {
 
     val localResult = doCall(
-            yy@ fun xxx(): Int {
+            yy@ fun(): Int {
                 if (doNonLocal) {
                     return@test3 nonLocal
                 }