arm64: dts: ti: k3-j721e-common-proc-board: Add boot phase tag to SERDES3

arm64: dts: ti: k3-j721e-common-proc-board: Add boot phase tag to SERDES3

The USB0 instance of USB on J721E SoC can be used for USB DFU boot.
Since the USB Type-C interface on the J721E-EVM is connected to USB0 via
SERDES3, supporting USB DFU boot requires SERDES3 link associated with
USB0 to be functional at all stages of the USB DFU boot process. Thus,
add the "bootph-all" boot phase tag to "serdes3_usb_link" device-tree node.

Signed-off-by: Siddharth Vadapalli <s-vadapalli@ti.com>
Link: https://lore.kernel.org/r/20250209081738.1874749-2-s-vadapalli@ti.com
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>