vppinfra: add bihash_init2

vppinfra: add bihash_init2

Add controls to list / not list a specific bihash in clib_all_bihashes,
to immediately initialize a bihash.

clib_bihash_init2 is now the primary API. It takes a typical args_t
structure. clib_bihash_init becomes a compatibility widget. It
fabricates an args_t and calls init2...

Type: refactor
Ticket: VPP-1758

Signed-off-by: Dave Barach <[email protected]>
Change-Id: Ib3e1304884997cf7025af20bdc67a7dda290f15b
(cherry picked from commit bdf9b97774f02458ede6b7c7ae2d5728bddba000)