switch off rdroidtest

rdroidtest doesn't work correctly with on-device tests because they use
`panic = "abort"` and rdroidtest doesn't support `-Zpanic-abort-tests`
yet. The result is that all test failure look like a "native crash" and
the test infra cannot correctly track them via bugs or display them in
the UI.

The only `rdroidtest` specific feature we used was `ignore_if`. It is a
bit of a loss to have ignored tests reported as passing, but it is a
lesser evil in this case.

Bug: 291169704
Bug: 384438979
Test: atest libdm_rust.test
Change-Id: I23af380c79a87d246a1f50e163415021d7f5fa84
diff --git a/libs/devicemapper/src/lib.rs b/libs/devicemapper/src/lib.rs
index a8c2833..bc8a762 100644
--- a/libs/devicemapper/src/lib.rs
+++ b/libs/devicemapper/src/lib.rs
@@ -230,14 +230,10 @@
 }
 
 #[cfg(test)]
-rdroidtest::test_main!();
-
-#[cfg(test)]
 mod tests {
     use super::*;
     use crate::loopdevice::LoopConfigOptions;
     use crypt::{CipherType, DmCryptTargetBuilder};
-    use rdroidtest::{ignore_if, rdroidtest};
     use rustutils::system_properties;
     use std::fs::{read, File, OpenOptions};
     use std::io::Write;
@@ -294,25 +290,29 @@
         }
     }
 
-    #[rdroidtest]
+    #[test]
     fn mapping_again_keeps_data_xts() {
         mapping_again_keeps_data(&KEY_SET_XTS, "name1");
     }
 
-    #[rdroidtest]
-    #[ignore_if(!is_hctr2_supported())]
+    #[test]
     fn mapping_again_keeps_data_hctr2() {
+        if !is_hctr2_supported() {
+            return;
+        }
         mapping_again_keeps_data(&KEY_SET_HCTR2, "name2");
     }
 
-    #[rdroidtest]
+    #[test]
     fn data_inaccessible_with_diff_key_xts() {
         data_inaccessible_with_diff_key(&KEY_SET_XTS, "name3");
     }
 
-    #[rdroidtest]
-    #[ignore_if(!is_hctr2_supported())]
+    #[test]
     fn data_inaccessible_with_diff_key_hctr2() {
+        if !is_hctr2_supported() {
+            return;
+        }
         data_inaccessible_with_diff_key(&KEY_SET_HCTR2, "name4");
     }