mutime: Make Sinfo an imported constant

The subject info data structure is static and is not changed during
runtime. Make Sinfo an imported constant and adjust refinement of
abstract timer state and global contract of Hz function accordingly.
They are no longer volatile.

Change-Id: I5729bc7f2d77c5c51a6cab2edc7953e95c9e4d29
Signed-off-by: Adrian-Ken Rueegsegger <ken@codelabs.ch>
Reviewed-on: https://review.coreboot.org/c/libhwbase/+/38982
Tested-by: Nico Huber <nico.h@gmx.de>
Reviewed-by: Nico Huber <nico.h@gmx.de>
2 files changed