arm64: dts: allwinner: A100: Add PMU mode

Add the Performance Monitoring Unit (PMU) device tree node to the A100
.dtsi, which tells DT users which interrupts are triggered by PMU overflow
events on each core.

Signed-off-by: Yangtao Li <frank@allwinnertech.com>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Cody Eksal <masterr3c0rd@epochal.quest>
Link: https://patch.msgid.link/20241031070232.1793078-2-masterr3c0rd@epochal.quest


Signed-off-by: Chen-Yu Tsai <wens@csie.org>