Add (mostly) empty KeystoreDB struct.

The KeystoreDB struct contains the interface with sqlite.

This commit introduces the KeystoreDB object and a sqlite connection
but does not add any operations.

Bug: 159370859
Test: atest keystore2_test
Change-Id: Ie5ec091a01d25ecd520ac29be67117cc3c3fd83c
diff --git a/keystore2/Android.bp b/keystore2/Android.bp
index bf78574..dd40589 100644
--- a/keystore2/Android.bp
+++ b/keystore2/Android.bp
@@ -21,13 +21,14 @@
         "libanyhow",
         "libkeystore_aidl_generated",
         "liblog_rust",
+        "librusqlite",
         "libthiserror",
     ],
 }
 
 rust_test {
     name: "keystore2_test",
-    crate_name: "keystore2_test",
+    crate_name: "keystore2",
     srcs: ["src/lib.rs"],
     test_suites: ["general-tests"],
     auto_gen_config: true,
@@ -36,6 +37,7 @@
         "libanyhow",
         "libkeystore_aidl_generated",
         "liblog_rust",
+        "librusqlite",
         "libthiserror",
     ],
 }