[JVM IR] Stabilize accesor names in IR Backend

- introduce a scoped counter instead of a global one for name
  generation for accessors. Naive solution not working.

- Introduced hardcoded "jd" suffix for accessors on interfaces, under
  the assumption that the only such accessors are due to JvmDefault
  and their bridges from `$DefaultImpls`. Removed all associated
  templated tests, so the old and IR backend correspond on this matter
  again.

- Respecialized writeFlags from regexps to string-equality: we are
  going for exact matches now!

- Fixed package calculation in `IrUtils.kt`.

- Accessors for static members must be due to accessing super
  classes. Actual super-qualified calls are naturally also accessing
  super classes. Hence the `$s+{hashcode(superClassName)}`
  suffix. Added test to affirm this naming scheme.

- Field getters/setters for static fields must be companion accessors,
  otherwise just labelled as accessors. They are also tagged with `s`
  suffix when accessing static fields.

- For naming of accessors to coincide with the old backend, field
  renaming to avoid JVM signature clashes must be done _after_
  generation of accessors for those fields.

compiler/testData/codegen/bytecodeText/companion/kt14258_2.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JVM_IR
 // Checks that methods 'access$getMy$p' and 'getMy' are not generated and
 // that backed field 'my' is accessed through 'access$getMy$cp'
 

compiler/testData/codegen/bytecodeText/companion/kt14258_3.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JVM_IR
 // Checks that accessor methods are always used due to the overriding of the default setter of 'my' property.
 
 class My {
@@ -19,11 +18,17 @@ class My {
     // GETSTATIC My.my into 'access$getMy$cp'
 }
 
-// 2 GETSTATIC My.my
 // 2 PUTSTATIC My.my
 // 0 INVOKESTATIC My\$Companion.access\$getMy\$p
-// 1 INVOKESTATIC My\$Companion.access\$setMy\$p
 // 1 INVOKESTATIC My.access\$setMy\$cp
+// 1 INVOKESPECIAL My\$Companion.setMy
+
+// JVM_TEMPLATES
+// 2 GETSTATIC My.my
+// 1 INVOKESTATIC My\$Companion.access\$setMy\$p
 // 1 INVOKESTATIC My.access\$getMy\$cp
 // 1 INVOKESPECIAL My\$Companion.getMy
-// 1 INVOKESPECIAL My\$Companion.setMy
+
+// IR only generates the accessors actually needed
+// JVM_IR_TEMPLATES
+// 1 GETSTATIC My.my

compiler/testData/codegen/bytecodeText/companion/kt14258_4.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JVM_IR
 // Checks that accessor 'I$Companion.access$getBar\$p' is always used because the property is kept
 // into the companion object.