dt-bindings: riscv: sifive: add YAML documentation for the SiFive FU540

Add YAML DT binding documentation for the SiFive FU540 SoC.  This
SoC is documented at:

    https://static.dev.sifive.com/FU540-C000-v1.0.pdf

Passes dt-doc-validate, as of yaml-bindings commit 4c79d42e9216.

Signed-off-by: Paul Walmsley <[email protected]>
Signed-off-by: Paul Walmsley <[email protected]>
Reviewed-by: Rob Herring <[email protected]>
Cc: Rob Herring <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Palmer Dabbelt <[email protected]>
Cc: Albert Ou <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]

0 files changed, 0 insertions, 0 deletions