[BOLT] Do not assert on jump table heuristic failure

Summary:
During the initial indirect jump analysis, we used to assert that the
discovered jump table type matched the pattern of the corresponding
instruction sequence. E.g., for PIC jump table memory we expected the
PIC jump table instruction sequence. The assertions were too
conservative, as in the case of a mismatch we can mark the indirect jump
as having an unknown control flow. That should be sufficient to either
skip the function processing or rely on relocation information for
possible recovery of the control flow.

(cherry picked from FBD27255816)