Revert "x86, apic: Use logical flat on intel with <= 8 logical cpus"

Revert "x86, apic: Use logical flat on intel with <= 8 logical cpus"

Revert commit 2fbd07a5f5d1295fa9b0c0564ec27da7c276a75a, as this commit
breaks an IBM platform with quad-core Xeon cpu's.

According to Suresh, this might be an IBM platform issue, as on other
Intel platforms with <= 8 logical cpu's, logical flat mode works fine
irespective of physical apic id values (inline with the xapic
architecture).

Revert this for now because of the IBM platform breakage.

Another version will be re-submitted after the complete analysis.

Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>