Revert "irqchip/riscv-imsic: Embed the vector array in lpriv"

Revert "irqchip/riscv-imsic: Embed the vector array in lpriv"

The __alloc_percpu() fails when the number of IDs are greater than 959
because size parameter of __alloc_percpu() must be less than 32768 (aka
PCPU_MIN_UNIT_SIZE). This failure is observed with KVMTOOL when AIA is
trap-n-emulated by in-kernel KVM because in this case KVM guest has 2047
interrupt IDs.

To address this issue, don't embed vector array in struct imsic_local_priv
until __alloc_percpu() support size parameter greater than 32768.

This reverts commit 79eaabc61dfb ("irqchip/riscv-imsic: Embed the vector
array in lpriv").

Signed-off-by: Anup Patel <anup.patel@oss.qualcomm.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Link: https://patch.msgid.link/20251223143544.1504217-1-anup.patel@oss.qualcomm.com