pldmd: Migrate instance ID allocation to pldm::InstanceIdDb

This removes use of `pldm::dbus_api::Requester` from around the
code-base. This makes progress towards removing the DBus API entirely
once all its consumers are converted to the libpldm instance ID APIs.

There was never a good reason for the code using the class to have
knowledge that it was related to DBus anyway, so this is, in-effect, a
double clean up improving separation of concerns.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Change-Id: I2d9397cae1b3c8c251c32e36ca520aad9c9b8cf6
diff --git a/libpldmresponder/base.hpp b/libpldmresponder/base.hpp
index 9a13f2d..2f7c714 100644
--- a/libpldmresponder/base.hpp
+++ b/libpldmresponder/base.hpp
@@ -13,7 +13,6 @@
 
 #include <vector>
 
-using namespace pldm::dbus_api;
 using namespace pldm::responder;
 
 namespace pldm
@@ -25,11 +24,12 @@
 class Handler : public CmdHandler
 {
   public:
-    Handler(uint8_t eid, Requester& requester, sdeventplus::Event& event,
+    Handler(uint8_t eid, pldm::InstanceIdDb& instanceIdDb,
+            sdeventplus::Event& event,
             pldm::responder::oem_platform::Handler* oemPlatformHandler,
             pldm::requester::Handler<pldm::requester::Request>* handler) :
         eid(eid),
-        requester(requester), event(event),
+        instanceIdDb(instanceIdDb), event(event),
         oemPlatformHandler(oemPlatformHandler), handler(handler)
     {
         handlers.emplace(PLDM_GET_PLDM_TYPES,
@@ -94,10 +94,8 @@
     /** @brief MCTP EID of host firmware */
     uint8_t eid;
 
-    /** @brief reference to Requester object, primarily used to access API to
-     *  obtain PLDM instance id.
-     */
-    Requester& requester;
+    /** @brief An instance ID database for allocating instance IDs. */
+    InstanceIdDb& instanceIdDb;
 
     /** @brief reference of main event loop of pldmd, primarily used to schedule
      *  work