validation: system: manually cast char to int
validation: system: manually cast char to int

On some systems, char is mapped to unsigned char which causes gcc to issue this warning:
test/validation/ver_abt_log_dbg/odp_system.c:23:7: error: array subscript has type ‘char’ [-Werror=char-subscripts]
Manually casting from char to int should fix issue on both (signed or unsigned) types of system

Signed-off-by: Nicolas Morey-Chaisemartin <7188b998d7bb37a035517aa285fa3f5a95344e80@kalray.eu>
Reviewed-by: Mike Holmes <ed44c09f4d7f698f5510adc894a872c73e08c8bd@linaro.org>
Signed-off-by: Maxim Uvarov <db4d16e02ae2d7493db430203537da8b2e34f290@linaro.org>

erachmi/odp,ravineet-singh/odp,nmorey/odp,rsalveti/odp,kalray/odp-mppa,kalray/odp-mppa,kalray/odp-mppa,erachmi/odp,mike-holmes-linaro/odp,kalray/odp-mppa,kalray/odp-mppa,mike-holmes-linaro/odp,rsalveti/odp,dkrot/odp,nmorey/odp,ravineet-singh/odp,kalray/odp-mppa,erachmi/odp,kalray/odp-mppa,dkrot/odp,mike-holmes-linaro/odp,mike-holmes-linaro/odp,rsalveti/odp,erachmi/odp,dkrot/odp,nmorey/odp,rsalveti/odp,dkrot/odp,ravineet-singh/odp,ravineet-singh/odp,nmorey/odp,rsalveti/odp