arm64: dts: ti: k3-j721s2: Add MCSPI nodes

arm64: dts: ti: k3-j721s2: Add MCSPI nodes

J721S2 has 8 MCSPI instances in the main domain and 3 instances
in the MCU domain. Add the DT nodes for all the 11 instances and
keep them disabled. MAIN_MCSPI4 is connected as a slave to MCU_MCSPI2
by default at power-up, MAIN_MCSPI4 and MCU_MCSPI2 are not pinned out
externally.

Signed-off-by: Vaishnav Achath <vaishnav.a@ti.com>
Reviewed-by: Keerthy <j-keerthy@ti.com>
Link: https://lore.kernel.org/r/20230321082827.14274-4-vaishnav.a@ti.com
Signed-off-by: Nishanth Menon <nm@ti.com>