hwLswSysMemory
1.3.6.1.4.1.43.45.1.2.23.1.18.1.14
The memory of system.
Note that the system memory means the memory can be used by the software
platform.
For the distributed device, it represents the memory size on the master
slot.
If the amount of system memory exceeds 4,294,967,295 bytes,
the value remains 4,294,967,295 bytes.