keymaster: add shared definition file keymaster.h

Bug: 74503339
Test: runtests pass

Change-Id: I632fe72c925e605a47235bdb9b11bb436f42ee24
diff --git a/nugget/include/keymaster.h b/nugget/include/keymaster.h
new file mode 100644
index 0000000..727fc82
--- /dev/null
+++ b/nugget/include/keymaster.h
@@ -0,0 +1,17 @@
+#ifndef NUGGET_KEYMASTER_H
+#define NUGGET_KEYMASTER_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+enum {
+  KM_MNF_DEVICE_ID_VERSION = 1,
+  KM_MNF_MAX_ENTRY_SIZE = 30
+};
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif