With the exception of one case in read_bndcfgu() which can use ilog2(),
the *_POS defines are unused. Drop them.
X86_XCR0_X87 is the name used by both the SDM and APM, rather than
X86_XCR0_FP.
No functional change.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> Acked-by: Jan Beulich <jbeulich@suse.com> Release-Acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com>