aarch64: Fix warnings
aarch64: Fix warnings

BUG=none
TEST=emerge-kukui crosvm

Change-Id: I6d4eb3655cad7b5f2dbfa6f3315482b50fe033f5
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosvm/+/3270098
Tested-by: kokoro <2ac7b1f3fa578934c95181d4272be0d3bca00121@google.com>
Commit-Queue: Chirantan Ekbote <35787c0e27de5c48735e07f8324823b765e8bcbc@chromium.org>
Reviewed-by: Daniel Verkamp <72bc170b46ec491f7bdd4359a1c0bfed274de40c@chromium.org>
Reviewed-by: Keiichi Watanabe <815e4e8f7c92a23424d7c3f51ead622bcedbc720@chromium.org>

google/crosvm,google/crosvm,google/crosvm,google/crosvm