fconf: Clean confused naming between TB_FW and FW_CONFIG

Cleaned up confused naming between TB_FW and FW_CONFIG.

Signed-off-by: Louis Mayencourt <louis.mayencourt@arm.com>
Signed-off-by: Manish V Badarkhe <Manish.Badarkhe@arm.com>
Change-Id: I9e9f6e6ca076d38fee0388f97d370431ae067f08
13 files changed