fix compiler warnings

Fix a couple unused-parameter warnings so we can turn the warnings all
the way up.

Change-Id: I36c611da5a10732dbb89e289e42a870c902dd245
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
diff --git a/mmc/item_updater_mmc.cpp b/mmc/item_updater_mmc.cpp
index 4d70ccf..3e58612 100644
--- a/mmc/item_updater_mmc.cpp
+++ b/mmc/item_updater_mmc.cpp
@@ -42,7 +42,7 @@
     return version;
 }
 
-bool ItemUpdaterMMC::validateImage(const std::string& path)
+bool ItemUpdaterMMC::validateImage(const std::string&)
 {
     return true;
 }
@@ -58,7 +58,7 @@
     return versionId == functionalVersionId;
 }
 
-void ItemUpdaterMMC::freePriority(uint8_t value, const std::string& versionId)
+void ItemUpdaterMMC::freePriority(uint8_t, const std::string&)
 {}
 
 void ItemUpdaterMMC::deleteAll()
@@ -69,7 +69,7 @@
     return true;
 }
 
-void ItemUpdaterMMC::updateFunctionalAssociation(const std::string& versionId)
+void ItemUpdaterMMC::updateFunctionalAssociation(const std::string&)
 {}
 
 void GardResetMMC::reset()