Fix two bugs that would allow changing the state of SGIs through the
ICPENDR and ISPENDRs.
Signed-off-by: NChristoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>