lib: move bsearch code

lib: move bsearch code

Convert this code to an inline function (backed by an instance in an
archive in case the compiler decides against inlining), which results
in not having it in x86 final binaries. This saves a little bit of dead
code.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Wei Liu <wl@xen.org>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>