Drop old enum syntax. Comma / semicolon are now a syntactic part of enum entry.

Comma must present now between enum entries, semicolon between last entry & first member, constructor calls must be without colons / specifiers.
A swarm of tests fixed accordingly.

compiler/testData/loadJava/compiledKotlin/fromLoadJava/enum.kt

@@ -1,6 +1,7 @@
+// ALLOW_AST_ACCESS
 package test
 
 enum class Test(a : Int) {
-  A : Test(0)
-  B : Test(0) {}
+  A(0),
+  B(0) {}
 }