crypto: octeontx2 - prevent underflow in get_cores_bmap()

commit 5f4d5fdae69e5837c67139222bdb08023073b82d from
git@git.assembla.com:cavium/WindRiver.linux.git

If we're going to cap "eng_grp->g->engs_num" upper bounds then we should
cap the lower bounds as well.

Fixes: 43ac0b82 ("crypto: octeontx2 - load microcode and create
engine groups")

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Change-Id: I034a848342fe09ed4f092aac2d9b5724239a5c52
Reviewed-on: https://sj1git1.cavium.com/c/IP/SW/kernel/linux/+/90677


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: Wenlin Kang <wenlin.kang@windriver.com>