Commit b4d5bf0aab96508f ("arm64: disable Broadcom Vulcan platform")
did not remove the ARCH_VULCAN configuration symbol, as there were still
references to this symbol.
As of commits f6b435883a79e0d0 ("gpio: xlp: update GPIO_XLP dependency") and 7cabbe2302a63a9f ("arm64: defconfig: drop ARCH_VULCAN"), the last users
of ARCH_VULCAN have been removed.