Replacing manual CBOR with serde-cbor

This change strips out all of the manually written CBOR parsing and
serialization code in favor of using the serde-cbor library in order to
make the code more robust and the error messages more actionable.

Fixes: 180392379
Test: atest RemoteProvisionerUnitTests
Change-Id: I1b08b26b6192763e393b061cd9b919cfd71c13c9
diff --git a/keystore2/Android.bp b/keystore2/Android.bp
index e8cdb6c..3b79334 100644
--- a/keystore2/Android.bp
+++ b/keystore2/Android.bp
@@ -52,6 +52,8 @@
         "liblog_rust",
         "librand",
         "librustutils",
+        "libserde",
+        "libserde_cbor",
         "libthiserror",
     ],
     shared_libs: [