KVM: ia64: fix ia64 build due to missing kallsyms_lookup() and double export

Fix problem with double export of certain symbols from vsprintf.c
which we do not wish to export from the kvm-intel.ko module.

In addition, we do not have access to kallsyms_lookup() from the
module, so make sure to #undef CONFIG_KALLSYMS

Signed-off-by: Jes Sorensen <jes@sgi.com>
Acked-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>