x86/alternatives: Simplify _apply_alternatives() now altcall is separate
With altcall handled separately, the special case in _apply_alternatives() is
unused and can be dropped. The force parameter (used to signify the seal
pass) can be removed too.
In turn, nmi_apply_alternatives() no longer needs to call
_apply_alternatives() on the second pass.
No functional change.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com> Reviewed-by: Jan Beulich <jbeulich@suse.com>