Remove unreachable code branch in line 163:
if CR0 enabled WP, supervisor-mode writing a read-only page have
been checked in line 109.
Merge redundant checking:
if smap is enabled, supervisor-mode can't access user-mode address
when eflags.ac disabled.
Tracked-On: #8708
Signed-off-by: Haoyu Tang <haoyu.tang@intel.com>