Drop is_leaf() check now that modify_range() returns leaves only

Test: build tested only
Change-Id: Ie740b0c7e56fce4456be400a811398f155eb74f6
diff --git a/vmbase/src/memory/dbm.rs b/vmbase/src/memory/dbm.rs
index 45f409c..108cd5d 100644
--- a/vmbase/src/memory/dbm.rs
+++ b/vmbase/src/memory/dbm.rs
@@ -14,7 +14,7 @@
 
 //! Hardware management of the access flag and dirty state.
 
-use super::page_table::{is_leaf_pte, PageTable};
+use super::page_table::PageTable;
 use super::util::flush_region;
 use crate::{dsb, isb, read_sysreg, tlbi, write_sysreg};
 use aarch64_paging::paging::{Attributes, Descriptor, MemoryRegion};
@@ -67,12 +67,9 @@
 pub(super) fn mark_dirty_block(
     va_range: &MemoryRegion,
     desc: &mut Descriptor,
-    level: usize,
+    _level: usize,
 ) -> Result<(), ()> {
     let flags = desc.flags().ok_or(())?;
-    if !is_leaf_pte(&flags, level) {
-        return Ok(());
-    }
     if flags.contains(Attributes::DBM) {
         assert!(flags.contains(Attributes::READ_ONLY), "unexpected PTE writable state");
         desc.modify_flags(Attributes::empty(), Attributes::READ_ONLY);
diff --git a/vmbase/src/memory/page_table.rs b/vmbase/src/memory/page_table.rs
index e355d4d..060d2d8 100644
--- a/vmbase/src/memory/page_table.rs
+++ b/vmbase/src/memory/page_table.rs
@@ -138,14 +138,3 @@
         self.idmap.walk_range(range, &mut callback)
     }
 }
-
-/// Checks whether a PTE at given level is a page or block descriptor.
-#[inline]
-pub(super) fn is_leaf_pte(flags: &Attributes, level: usize) -> bool {
-    const LEAF_PTE_LEVEL: usize = 3;
-    if flags.contains(Attributes::TABLE_OR_PAGE) {
-        level == LEAF_PTE_LEVEL
-    } else {
-        level < LEAF_PTE_LEVEL
-    }
-}