arm64: dts: ti: k3-j721s2-som-p0: Update mux-controller node name

arm64: dts: ti: k3-j721s2-som-p0: Update mux-controller node name

There are 2 mux-controller nodes in J721S2 which are responsible for
transferring can signals to the can phy but same node names for both
the mux-controllers led to errors while setting up both mux-controllers
for can phys simultaneously.
Thus, update node names for these mux-controller.

Fixes: 98f3b667e1de ("arm64: dts: ti: k3-j721s2: Add support for CAN instances 3 and 5 in main domain")
Signed-off-by: Bhavya Kapoor <b-kapoor@ti.com>
Link: https://lore.kernel.org/r/20240729063411.1570930-2-b-kapoor@ti.com
Signed-off-by: Nishanth Menon <nm@ti.com>