Refactor status package to use portbase/runtime.

Refactor the status package to use portbase/runtime and
make system status readonly. Also adapts the code base
to the new portbase/notifications package.

status/state.go

@@ -0,0 +1,30 @@
+package status
+
+import (
+	"sync/atomic"
+)
+
+var (
+	activeLevel   = new(uint32)
+	selectedLevel = new(uint32)
+)
+
+func setActiveLevel(lvl uint8) {
+	atomic.StoreUint32(activeLevel, uint32(lvl))
+}
+
+func setSelectedLevel(lvl uint8) {
+	atomic.StoreUint32(selectedLevel, uint32(lvl))
+}
+
+// ActiveSecurityLevel returns the currently active security
+// level.
+func ActiveSecurityLevel() uint8 {
+	return uint8(atomic.LoadUint32(activeLevel))
+}
+
+// SelectedSecurityLevel returns the security level as selected
+// by the user.
+func SelectedSecurityLevel() uint8 {
+	return uint8(atomic.LoadUint32(selectedLevel))
+}