i386: Helpers to encode cache information consistently

i386: Helpers to encode cache information consistently

Instead of having a collection of macros that need to be used in
complex expressions to build CPUID data, define a CPUCacheInfo
struct that can hold information about a given cache.  Helper
functions will take a CPUCacheInfo struct as input to encode
CPUID leaves for a cache.

This will help us ensure consistency between cache information
CPUID leaves, and make the existing inconsistencies in CPUID info
more visible.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Babu Moger <babu.moger@amd.com>
Tested-by: Geoffrey McRae <geoff@hostfission.com>
Message-Id: <20180510204148.11687-2-babu.moger@amd.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>