Move all of the ARM-specific initialization into one function namely
acpi_arm_init(), so it is not necessary to modify/update bus.c every
time a new piece of it is added.

Cc: Lorenzo Pieralisi <lpieralisi@kernel.org>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Hanjun Guo <guohanjun@huawei.com>
Link: https://lore.kernel.org/r/CAJZ5v0iBZRZmV_oU+VurqxnVMbFN_ttqrL=cLh0sUH+=u0PYsw@mail.gmail.comSigned-off-by: Sudeep Holla <sudeep.holla@arm.com>
Reviewed-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Reviewed-by: Shaoqin Huang <shahuang@redhat.com>
Link: https://lore.kernel.org/r/20230606093531.2746732-1-sudeep.holla@arm.comSigned-off-by: Catalin Marinas <catalin.marinas@arm.com>