Merge branch 'sparc64-jump-to-boot-prom'

Merge branch 'sparc64-jump-to-boot-prom'

Vijay Kumar says:

====================
sparc64: Jump to boot prom from console on panic

V3 changes:
  - patch 02/04: Added SERIAL_SUNHV conditional group for
    sunhv_migrate_hvcons_irq in smp_send_stop().
V2 changes:
 -  Added cover letter patch

Currently Stop-A (L1A) does not make the kernel switch to OBP on panic. This
patchset addresses this issue. Also, now we can cause a jump to OBP by sending
'break' twice from sunhv console. On bare metal, one can send a break by
typing Esc + 'B' + Sysrq (or whatever). On LDOM, press Ctrl + ] in telnet,
and then "send break" at the telnet prompt.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>