- The debugging banner helpers *CANNOT* be in the INIT section, because
it is possible for KdInitSystem() to enable the debugger **MUCH LATER**
after boot time. (Reverts part of commit f239ca0f0 (r72922).)
This can happen in two situations:
* When the debugger is in CRASHDEBUG mode, i.e. initialized at boot
time but not immediately enabled, and a BSOD happens later that
enables the debugger with a `KdInitSystem(0, NULL)` call.
* When the debugger was possibly manually disabled with a
KdDisableDebugger() call, then later re-enabled with a
KdEnableDebugger() call.
- In the same cases as described above, the KeLoaderBlock is freed after
boot time. Thus, KdpGetMemorySizeInMBs() cannot use it and enumerate
the MemoryDescriptors to evaluate the number of physical memory pages
available on the system. Instead, we can use what the memory manager
has already computed, since the latter is already initialized by now.
These two fixes avoid (invisible) crashes when (re-)enabling
the debugger at non-boot run time.