target/arm/kvm: Init cap_has_inject_serror_esr in kvm_arch_init

target/arm/kvm: Init cap_has_inject_serror_esr in kvm_arch_init

There is no need to do this in kvm_arch_init_vcpu per vcpu.
Inline kvm_arm_init_serror_injection rather than keep separate.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Tested-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>