crypto: sun8i-ss - Move j init earlier in sun8i_ss_hash_run

crypto: sun8i-ss - Move j init earlier in sun8i_ss_hash_run

With gcc-14 I get

../drivers/crypto/allwinner/sun8i-ss/sun8i-ss-hash.c: In function ‘sun8i_ss_hash_run’:
../drivers/crypto/allwinner/sun8i-ss/sun8i-ss-hash.c:631:21: warning: ‘j’ may be used uninitialized [-Wmaybe-uninitialized]
  631 |                 j = hash_pad(bf, 4096, j, byte_count, true, bs);
      |                     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../drivers/crypto/allwinner/sun8i-ss/sun8i-ss-hash.c:493:13: note: ‘j’ was declared here
  493 |         int j, i, k, todo;
      |             ^

Fix this false positive by moving the initialisation of j earlier.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>