ia64: add jump labels for paravirt

Since in a later patch I intend to call jump labels inside
CONFIG_PARAVIRT, IA64 would fail to compile if they are not
provided. This patch provides those jump labels for the IA64
architecture.

Signed-off-by: Glauber Costa <glommer@redhat.com>
Acked-by: Isaku Yamahata <yamahata@valinux.co.jp>
Acked-by: Rik van Riel <riel@redhat.com>
CC: Tony Luck <tony.luck@intel.com>
CC: Eddie Dong <eddie.dong@intel.com>
CC: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
CC: Peter Zijlstra <peterz@infradead.org>
CC: Anthony Liguori <aliguori@us.ibm.com>
CC: Eric B Munson <emunson@mgebm.net>
Signed-off-by: Avi Kivity <avi@redhat.com>