drivers: firmware: octeontx2: Adding mub_gen dependency

commit d59ce520b28de2050e988c3d049a00f45da7b178 from
git@git.assembla.com:cavium/WindRiver.linux.git

Adding module dependency of mub_gen driver in memtest module

Signed-off-by: Piyush Malgujar <pmalgujar@marvell.com>
Change-Id: Ie2bb5dfc2ee4a5c0db479e8ca2a8048facc6183e
Reviewed-on: https://sj1git1.cavium.com/c/IP/SW/kernel/linux/+/85799
Reviewed-by: Chandrakala Chavva <cchavva@marvell.com>
Tested-by: sa_ip-sw-jenkins <sa_ip-sw-jenkins@marvell.com>
Reviewed-on: https://sj1git1.cavium.com/c/IP/SW/kernel/linux/+/120333
Reviewed-by: Sunil Kovvuri Goutham <sgoutham@marvell.com>
Signed-off-by: Ruiqiang Hao <Ruiqiang.Hao@windriver.com>