x86/crypto/crc32c-pcl-intel: Standardize jump table

Simplify the jump table code so that it resembles a compiler-generated
table.

This enables ORC unwinding by allowing objtool to follow all the
potential code paths.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Tested-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Sami Tolvanen <samitolvanen@google.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Link: https://lore.kernel.org/r/5357a039def90b8ef6b5874ef12cda008ecf18ba.1614182415.git.jpoimboe@redhat.com