arm: mach-k3: j7200: Detect if ROM has already loaded sysfw

Detect if sysfw is already loaded by ROM and pass this information to
sysfw loader. Based on this information sysfw loader either loads the
sysfw image from boot media or just receives the boot notification
message form sysfw.

Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Reviewed-by: Suman Anna <s-anna@ti.com>