cpu: use typedefs for enums in "src/cpu/cpu_map.h"

cpu: use typedefs for enums in "src/cpu/cpu_map.h"

In "src/cpu/" there are some enumerations (enum) declarations.
Similar to the recent cleanup to "src/util", "src/conf" and other
directories, it's better to use a typedef for variable types,
function types and other usages. Other enumeration and folders will
be changed to typedef's in the future. Specially, in files that are
in different places of "src/util" and "src/conf". Most of the files
changed in this commit are related to CPU (cpu_map.h) enums.

Signed-off-by: Julio Faracco <jcfaracco@gmail.com>