Change the intel cpu makefile.inc so that it fits the model better.

Change the intel cpu makefile.inc so that it fits the model better.
- intel/Makefile.inc only mentions sockets
- those sockets are conditionally included
- makefile.inc in socket directories are almost all unconditionally included
- Get rid of if where possible, use -$(CONFIG_VARIABLE) instead as per Kconfig
  standards in linux kernel

See the Kconfig.tex documentation for questions.

Signed-off-by: Ronald G. Minnich <rminnich@gmail.com>
Acked-by: Patrick Georgi <patrick.georgi@coresystems.de>
git-svn-id: svn://svn.coreboot.org/coreboot/trunk@4561 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1