target/arm: Handle IS/FS in ISR_EL1 for NMI, VINMI and VFNMI

target/arm: Handle IS/FS in ISR_EL1 for NMI, VINMI and VFNMI

Add IS and FS bit in ISR_EL1 and handle the read. With CPU_INTERRUPT_NMI or
CPU_INTERRUPT_VINMI, both CPSR_I and ISR_IS must be set. With
CPU_INTERRUPT_VFNMI, both CPSR_F and ISR_FS must be set.

Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20240407081733.3231820-9-ruanjinjie@huawei.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>