x86/alternative: Drop unused feature parameter from ALTINSTR_REPLACEMENT()

The macro ALTINSTR_REPLACEMENT() doesn't make use of the feature
parameter, so drop it.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210309134813.23912-4-jgross@suse.com