[NTOS:CM] Implement support for alternate registry hives

Sometimes repairing a broken hive with a hive log does not always guarantee the hive
in question has fully recovered. In worst cases it could happen the LOG itself is even
corrupt too and that would certainly lead to a total unbootable system. This is most likely
if the victim hive is the SYSTEM hive.

This can be anyhow solved by the help of a mirror hive, or also called an "alternate hive".
Alternate hives serve the purpose as backup hives for primary hives of which there is still
a risk that is not worth taking. For now only the SYSTEM hive is granted the right to have
a backup alternate hive.

=== NOTE ===

Currently the SYSTEM hive can only base upon the alternate SYSTEM.ALT hive, which means the
corresponding LOG file never gets updated. When time comes the existing code must be adapted
to allow the possibility to use .ALT and .LOG hives simultaneously.

sdk/lib/cmlib/cmlib.h

@@ -120,6 +120,10 @@
         IN ULONG StartingIndex,
         IN ULONG NumberToSet);
 
+    VOID NTAPI
+    RtlSetAllBits(
+        IN PRTL_BITMAP BitMapHeader);
+
     VOID NTAPI
     RtlClearAllBits(
         IN PRTL_BITMAP BitMapHeader);
@@ -509,6 +513,11 @@ BOOLEAN CMAPI
 HvWriteHive(
    PHHIVE RegistryHive);
 
+BOOLEAN
+CMAPI
+HvWriteAlternateHive(
+    _In_ PHHIVE RegistryHive);
+
 BOOLEAN
 CMAPI
 HvSyncHiveFromRecover(