This breaks ARM. It should be protected by some x86 #if. For now,
revert it, as it's not critical (and it isn't included in the
comet/vixen security patch branches published via XSA-254).
This reverts commit 63080b7043.
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
CC: Wei Liu <wei.liu2@citrix.com>
CC: Julien Grall <julien.grall@linaro.org>