ARM: config: aspeed: Update defconfig

 - Enable new support:
     hardware random number generator
     FSI and client drivers
     DRM GFX driver

 - Disable unwanted features:
     ARM_APPENDED_DTB
     ARM_ATAG_DTB_COMPAT
     BLK_DEV_RAM

 - Sync G4 and G5 with OpenBMC configurations
     BLK_DEV_LOOP, for updater mechanic
     CRYPTO_HMAC, for libsdbus features
     CRYPTO_SHA256
     CRYPTO_USER_API_HASH

 - Enable security related features:
     SLAB_FREELIST_RANDOM
     STRICT_KERNEL_RW
     CC_STACKPROTECTOR_STRONG
     HARDENED_USERCOPY
     FORTIFY_SOURCE

 - Increase kernel log buffer size

Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Joel Stanley <joel@jms.id.au>