FIR checker: add diagnostic CANNOT_WEAKEN_ACCESS_PRIVILEGE

compiler/testData/diagnostics/tests/scopes/VisibilityInheritModifier.fir.kt

@@ -65,7 +65,7 @@ open class L : T {
 }
 
 class M : L() {
-    internal override fun foo() {}
+    <!CANNOT_WEAKEN_ACCESS_PRIVILEGE!>internal<!> override fun foo() {}
 }
 //---------------
 interface R {
@@ -81,5 +81,5 @@ interface Q : R {
 }
 
 class S : P, Q {
-    internal override fun foo() {}
+    <!CANNOT_WEAKEN_ACCESS_PRIVILEGE!>internal<!> override fun foo() {}
 }

compiler/testData/diagnostics/tests/scopes/kt1248.fir.kt

@@ -1,12 +0,0 @@
-//KT-1248 Control visibility of overrides needed
-package kt1248
-
-interface ParseResult<out T> {
-    public val success : Boolean
-    public val value : T
-}
-
-class Success<T>(internal override val value : T) : ParseResult<T> {
-    internal override val success : Boolean = true
-}
-

compiler/testData/diagnostics/tests/scopes/kt1248.kt

@@ -1,3 +1,4 @@
+// FIR_IDENTICAL
 //KT-1248 Control visibility of overrides needed
 package kt1248
 

compiler/testData/diagnostics/tests/scopes/kt151.fir.kt

@@ -28,11 +28,11 @@ class D : C(), T {
 }
 
 class E : C(), T {
-    internal override fun foo() {}
+    <!CANNOT_WEAKEN_ACCESS_PRIVILEGE!>internal<!> override fun foo() {}
 }
 
 class F : C(), T {
-    <!INCOMPATIBLE_MODIFIERS!>private<!> <!INCOMPATIBLE_MODIFIERS!>override<!> fun foo() {}
+    <!CANNOT_WEAKEN_ACCESS_PRIVILEGE, INCOMPATIBLE_MODIFIERS!>private<!> <!INCOMPATIBLE_MODIFIERS!>override<!> fun foo() {}
 }
 
 class G : C(), T {