crypto/cnxk: fix build with GCC 12

crypto/cnxk: fix build with GCC 12

The following warning is observed with GCC 12 compilation:

In file included from ../drivers/crypto/cnxk/cn10k_cryptodev_ops.c:17:
In function ‘fill_sg_comp_from_iov’,
    inlined from ‘cpt_pdcp_chain_alg_prep’ at
        ../drivers/crypto/cnxk/cnxk_se.h:1194:8,
    inlined from ‘cpt_fc_enc_hmac_prep’ at
        ../drivers/crypto/cnxk/cnxk_se.h:1871:9,
    inlined from ‘fill_digest_params’ at
        ../drivers/crypto/cnxk/cnxk_se.h:2829:8,
    inlined from ‘cpt_sym_inst_fill’ at
        ../drivers/crypto/cnxk/cn10k_cryptodev_ops.c:92:9,
    inlined from ‘cn10k_cpt_fill_inst.constprop’ at
        ../drivers/crypto/cnxk/cn10k_cryptodev_ops.c:146:10:
../drivers/crypto/cnxk/cnxk_se.h:222:52: warning: array subscript 0 is
outside array bounds of ‘struct roc_se_buf_ptr[0]’ [-Warray-bounds]
  222 |           e_vaddr = (uint64_t)bufs[j].vaddr;
      |                               ~~~~~~~^~~~~~
../drivers/crypto/cnxk/cnxk_se.h:223:48: warning: array subscript 0 is
outside array bounds of ‘struct roc_se_buf_ptr[0]’ [-Warray-bounds]
  223 |           e_len = (size > bufs[j].size) ? bufs[j].size : size;
      |                           ~~~~~~~^~~~~

This patch resolves the warning.

Fixes: 3de331795f73 ("crypto/cnxk: add flexi cipher encryption")
Cc: stable@dpdk.org
Signed-off-by: Ankur Dwivedi <adwivedi@marvell.com>
Reviewed-by: Anoob Joseph <anoobj@marvell.com>
Reviewed-by: Jerin Jacob <jerinj@marvell.com>
Tested-by: David Marchand <david.marchand@redhat.com>