AK+Kernel: Format DistinctNumeric using the underlying type's formatter

Forcing the formatting to go through `Formatter<FormatString>` is
completely unnecessary, increases code size, performs a String
allocation and prevents us from using the formatting options available
on that type.

This commit also removes explicit formatters from
`BlockBasedFileSystem::BlockIndex` and `Kernel::InodeIndex`, as those
are already covered by the blanket implementation for all
`DistinctNumeric` types.

AK/DistinctNumeric.h

@@ -270,10 +270,10 @@ private:
 };
 
 template<typename T, typename X, bool Incr, bool Cmp, bool Bool, bool Flags, bool Shift, bool Arith>
-struct Formatter<DistinctNumeric<T, X, Incr, Cmp, Bool, Flags, Shift, Arith>> : Formatter<FormatString> {
+struct Formatter<DistinctNumeric<T, X, Incr, Cmp, Bool, Flags, Shift, Arith>> : Formatter<T> {
     void format(FormatBuilder& builder, DistinctNumeric<T, X, Incr, Cmp, Bool, Flags, Shift, Arith> value)
     {
-        return Formatter<FormatString>::format(builder, "{}", value.value());
+        return Formatter<T>::format(builder, value.value());
     }
 };
 

Kernel/FileSystem/BlockBasedFileSystem.h

@@ -48,11 +48,3 @@ private:
 };
 
 }
-
-template<>
-struct AK::Formatter<Kernel::BlockBasedFileSystem::BlockIndex> : AK::Formatter<FormatString> {
-    void format(FormatBuilder& builder, Kernel::BlockBasedFileSystem::BlockIndex value)
-    {
-        return AK::Formatter<FormatString>::format(builder, "{}", value.value());
-    }
-};

Kernel/FileSystem/InodeIdentifier.h

@@ -61,11 +61,3 @@ struct AK::Formatter<Kernel::InodeIdentifier> : AK::Formatter<FormatString> {
         return AK::Formatter<FormatString>::format(builder, "{}:{}", value.fsid(), value.index());
     }
 };
-
-template<>
-struct AK::Formatter<Kernel::InodeIndex> : AK::Formatter<FormatString> {
-    void format(FormatBuilder& builder, Kernel::InodeIndex value)
-    {
-        return AK::Formatter<FormatString>::format(builder, "{}", value.value());
-    }
-};