arm64: defconfig: Enable TI PRUSS

The Programmable Realtime Unit - Industrial Communication Subsystem
(PRU-ICSS) known as PRUSS, is a low-latency microcontroller subsystem
used for industrial networking and other hard real-time functions in
the TI K3 SoCs such as AM654x, AM64x.

AM654x-EVM, AM64xx-EVM, and iot2050 use the PRUSS driver.

Signed-off-by: MD Danish Anwar <danishanwar@ti.com>
Reviewed-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Konrad Dybcio <konradybcio@kernel.org>
Link: https://lore.kernel.org/r/20230808130131.3081482-1-danishanwar@ti.com
Signed-off-by: Nishanth Menon <nm@ti.com>