change default build target to arm64

Author: thestinger

static/releases.html

@@ -586,6 +586,7 @@ <h3><a href="#2022090600">2022090600</a></h3>
                         <li>hardened_malloc: increase arm64 class region size to 32GB from 2GB to provide higher entropy random bases and higher memory allocation limits since all supported devices have a 48 bit address space now</li>
                         <li>add missing permission to allow Settings search (SettingsIntelligence) to query all apps</li>
                         <li>update GrapheneOS mask used for boot animation</li>
+                        <li>change default build target from aosp_arm to aosp_arm64</li>
                     </ul>
                 </article>
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