feat(rdfremont) enable the support to fetch dynamic config

To enable the support to load Hafnium as BL32, BL31 needs firmware
configuration info to get BL32 manifest load location. The load address
of BL32 is passed via firmware config info.

Add the support to get the address using fconf framework from dynamicn
config info.

Signed-off-by: Nishant Sharma <nishant.sharma@arm.com>