crypto: octeontx2 - out of bounds access in otx2_cpt_dl_custom_egrp_delete()

commit f7ab57a975402dfd373605ba43bd2284f313476b from
git@git.assembla.com:cavium/WindRiver.linux.git

If "egrp" is negative then it is causes an out of bounds access in
eng_grps->grp[].

Fixes: d9d77497 ("crypto: octeontx2 - add apis for custom engine groups")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Change-Id: I754ac7923d30143675d5f838d6422aab5776671b
Reviewed-on: https://sj1git1.cavium.com/c/IP/SW/kernel/linux/+/90413


Tested-by: sa_ip-sw-jenkins <sa_ip-sw-jenkins@marvell.com>
Reviewed-by: Nithin Kumar Dabilpuram <ndabilpuram@marvell.com>
Reviewed-by: Sunil Kovvuri Goutham <sgoutham@marvell.com>
Signed-off-by: Beniamin Sandu <beniamin.sandu@windriver.com>