Revert submission 3195358-ndk-libcxx
Reason for revert: Droidmonitor created revert due to b/356220894. Will be verifying through ABTD before submission.
Reverted changes: /q/submissionid:3195358-ndk-libcxx
Change-Id: If4bac6cca12a4c70bab22ffd310f262ef6f5fb78
Add barebones files to support building for a riscv64 target.
Bug: 250918230
Test: lunch aosp_riscv64-userdebug && m ALLOW_MISSING_DEPENDENCIES=true nothing
Change-Id: I61e6ecf6706b7682c77b07e6593d78c7d1eaef39