irqchip/starfive: Rename jh8100 to jhb100

irqchip/starfive: Rename jh8100 to jhb100

The StarFive JH8100 SoC was discontinued before production. The newly
taped-out JHB100 SoC uses the same interrupt controller IP.  Rename the
driver file, Kconfig symbol, and internal references from "jh8100" to
"jhb100" to accurately reflect the supported hardware.

Signed-off-by: Changhuang Liang <changhuang.liang@starfivetech.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20260416064751.632138-3-changhuang.liang@starfivetech.com