Add SecureAccess enum

Introduce SecureAccess enum to describe read/write access instead of
using a pair of booleans. This makes caller code more readable and
simplifies storage of access rights.

Signed-off-by: Imre Kis <imre.kis@arm.com>
Change-Id: Idbb675790043b5816325fe8132b021cd3a00a01d
diff --git a/src/lib.rs b/src/lib.rs
index 551dea9..b12ea45 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -17,7 +17,7 @@
 use zerocopy::{FromBytes, Immutable, IntoBytes, KnownLayout};
 
 pub use crate::fail::{FailAccessDirection, FailControlRegister, FailIDRegister, TzcFail};
-pub use crate::region::{RegionAttributes, RegionIDAccess, TzcRegion, TzcRegionMut};
+pub use crate::region::{RegionAttributes, RegionIDAccess, SecureAccess, TzcRegion, TzcRegionMut};
 use crate::{
     fail::FailRegisters,
     region::RegionRegisters,