dt-bindings: clock: Add StarFive JH7110 system clock and reset generator

Add bindings for the system clock and reset generator (SYSCRG) on the
JH7110 RISC-V SoC by StarFive Ltd.

Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Signed-off-by: Hal Feng <hal.feng@starfivetech.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>