arm64: dts: cavium: Drop thunder2

The Cavium thunder2 DT support is incomplete. It consists of 4 cores
(out of 128) and only a serial port. The thunder2 specific drivers in
the kernel don't have DT support either. The few remaining users of
this platform likely use ACPI.

Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
Link: https://patch.msgid.link/20251216180202.2794695-2-robh@kernel.org
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>

Author: robherring

arch/arm64/boot/dts/cavium/Makefile

@@ -1,3 +1,2 @@
 # SPDX-License-Identifier: GPL-2.0
 dtb-$(CONFIG_ARCH_THUNDER) += thunder-88xx.dtb
-dtb-$(CONFIG_ARCH_THUNDER2) += thunder2-99xx.dtb