Extend libdm_rust to build dm-crypt device

Add crypt module which supports building DmCryptTarget based dm table
entry. Also expose this via create_crypt_device()

Also, add unit test that use loopdevice as the backing device.

Test: atest libdm_rust.test
Bug: 250880499
Change-Id: Ibf09ca267cbcc7a2dc00dd835f2d8b781040f130
diff --git a/libs/devicemapper/Android.bp b/libs/devicemapper/Android.bp
index 088b320..783fa79 100644
--- a/libs/devicemapper/Android.bp
+++ b/libs/devicemapper/Android.bp
@@ -36,5 +36,5 @@
         "libscopeguard",
         "libtempfile",
     ],
-    data: ["tests/data/*"],
+    data: ["testdata/*"],
 }