Change per-boot tag and remove rescope auth timeout tag.

Change the boolean KM_TAG_SINGLE_USE_PER_BOOT to an integer-valued
KM_TAG_USES_PER_BOOT.  This makes it more flexible without changing
implementation complexity.

Remove KM_TAG_RESCOPE_AUTH_TIMEOUT because there's no clear use case and
it seems unnecessarily complex.

Change-Id: Iad1512f5cc80f517e5ea7622288179c162bed2ad
diff --git a/include/hardware/keymaster_defs.h b/include/hardware/keymaster_defs.h
index 3a0aecc..fb427a3 100644
--- a/include/hardware/keymaster_defs.h
+++ b/include/hardware/keymaster_defs.h
@@ -138,13 +138,13 @@
                                                            longer be trusted. */
     KM_TAG_MIN_SECONDS_BETWEEN_OPS = KM_INT | 403,      /* Minimum elapsed time between
                                                            cryptographic operations with the key. */
-    KM_TAG_SINGLE_USE_PER_BOOT = KM_BOOL | 404,         /* If true, the key can only be used once
-                                                           per boot. */
+    KM_TAG_MAX_USES_PER_BOOT = KM_INT | 404,            /* Number of times the key can be used per
+                                                           boot. */
 
     /* User authentication */
-    KM_TAG_ALL_USERS = KM_BOOL | 500, /* If key is usable by all users. */
-    KM_TAG_USER_ID = KM_INT | 501,    /* ID of authorized user.  Disallowed if KM_TAG_ALL_USERS is
-                                         present. */
+    KM_TAG_ALL_USERS = KM_BOOL | 500,           /* If key is usable by all users. */
+    KM_TAG_USER_ID = KM_INT | 501,              /* ID of authorized user.  Disallowed if
+                                                   KM_TAG_ALL_USERS is present. */
     KM_TAG_NO_AUTH_REQUIRED = KM_BOOL | 502,    /* If key is usable without authentication. */
     KM_TAG_USER_AUTH_ID = KM_INT_REP | 503,     /* ID of the authenticator to use (e.g. password,
                                                    fingerprint, etc.).  Repeatable to support
@@ -156,10 +156,6 @@
                                                    If absent, authentication is required for every
                                                    use.  Authentication state is lost when the
                                                    device is powered off. */
-    KM_TAG_RESCOPE_AUTH_TIMEOUT = KM_INT | 505, /* Required freshness of user authentication for key
-                                                   rescoping operations, in seconds.  Public key
-                                                   operations require no authentication.  If absent,
-                                                   authentication required for every rescoping. */
 
     /* Application access control */
     KM_TAG_ALL_APPLICATIONS = KM_BOOL | 600, /* If key is usable by all applications. */