Remove attestation, tpm_manager, trunks and add tpm to the manifest.

We recently moved attestation, tpm_manager and trunks into system/tpm,
so that they can live in one repo. This CL removes the old attestation,
tpm_manager and trunks repos from the manifest and adds the new tpm
repo.

Bug: 25820760
diff --git a/default.xml b/default.xml
index 8d27dfc..8f9576e 100644
--- a/default.xml
+++ b/default.xml
@@ -494,7 +494,6 @@
   <project path="prebuilts/sdk" name="platform/prebuilts/sdk" groups="pdk" />
   <project path="prebuilts/tools" name="platform/prebuilts/tools" groups="pdk,tools" />
   <project path="sdk" name="platform/sdk" groups="pdk-cw-fs,pdk-fs" />
-  <project path="system/attestation" name="platform/system/attestation" />
   <project path="system/bt" name="platform/system/bt" groups="pdk" />
   <project path="system/ca-certificates" name="platform/system/ca-certificates" groups="pdk" />
   <project path="system/connectivity/apmanager" name="platform/system/connectivity/apmanager" />
@@ -510,8 +509,7 @@
   <project path="system/netd" name="platform/system/netd" groups="pdk" />
   <project path="system/security" name="platform/system/security" groups="pdk" />
   <project path="system/tools/aidl" name="platform/system/tools/aidl" groups="pdk-cw-fs,pdk-fs" />
-  <project path="system/tpm_manager" name="platform/system/tpm_manager" />
-  <project path="system/trunks" name="platform/system/trunks" />
+  <project path="system/tpm" name="platform/system/tpm" />
   <project path="system/update_engine" name="platform/system/update_engine" />
   <project path="system/vold" name="platform/system/vold" groups="pdk" />
   <project path="system/weaved" name="platform/system/weaved" />