xen/control: print warning on call of xctrl_suspend()

[ehem_freebsd_m5p.com]

Summary

Presently suspend/resume and migration aren't supported on Xen/ARM. As
such this shouldn't ever occur.

Modified to check for ARM instead of !x86, since ARM is where support is
missing. Other Xen architectures might get suspend support sooner.

Submitted by: Elliott Mitchell <[e-mail]>
Original implementation: Julien Grall <[e-mail]>, 2014-01-13 17:41:15

[royger]

The commit message doesn't seem to match the actual code, it says: "implement suspend as panic for ARM" yet xctrl_suspend for Arm is just a printf, not a panic.

[ehem_freebsd_m5p.com]

Hopefully arc grabs the updated commit message, though I suspect I'll
need to manually update the message in Phabricator.

[ehem_freebsd_m5p.com]

Hopefully the updated commit message is okay. That one was the original line, I hadn't been paying too close attention since issues hadn't focused here.

[ehem_freebsd_m5p.com]

Switching back to checking for amd64 or i386. Likely
suspend/resume/migration won't immediately be supported for RISC-V.

Add machine/intr_machdep.h to guarded headers, this shouldn't be
#included in an architecture-independent file.