Introduce the main thread and HECI Active Management (HAM)
message handling for the ISSEI (Intel Silicon Security Engine
Interface) subsystem.
The main thread is responsible for managing the reset flow and
processing messages, while the HAM message handling is crucial
for initializing communication with the firmware and managing
clients.

With this implementation, the ISSEI driver is capable of performing
the required initialization and management of communication between
the host and the firmware.

Reviewed-by: Karol Wachowski <karol.wachowski@linux.intel.com>
Co-developed-by: Vitaly Lubart <lubvital@gmail.com>
Signed-off-by: Vitaly Lubart <lubvital@gmail.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Link: https://patch.msgid.link/20260513-issei-for-upstream-v1-3-f590038678f9@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The ISSEI (Intel Silicon Security Engine Interface)
subsystem provides a communication channel between the host and the
Silicon Security Engine.

Prepare basic driver functions and character device
for user-space communication.
Add DMA access routines for ISSEI HECI devices.
Add of DMA-related structures and implementation of routines for
setting up DMA, as well as reading and writing DMA buffers.

Reviewed-by: Karol Wachowski <karol.wachowski@linux.intel.com>
Co-developed-by: Vitaly Lubart <lubvital@gmail.com>
Signed-off-by: Vitaly Lubart <lubvital@gmail.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Link: https://patch.msgid.link/20260513-issei-for-upstream-v1-1-f590038678f9@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>