MFH: r431492 r431583

Fix sysutils/lsof on arm.

This fixes the case where ARM_NARCH and ARM_NMMUS are 0, since the lsof(1) sources get hacky
access to kernel structures.

PR: 216065
Submitted by: samm os2 kiev ua
Obtained from: Vic Abell (author)

Approved by: ports-secteam (blanket), adamw (mentor)