Update clang-tidy

Fix a bunch of minor issues, ignore others.  We use a lot of global
variables.  Enabling a check will hopefully make sure we don't add more.

Change-Id: Ie76053d4afc95a5372b70b2fb768be464468cec0
Signed-off-by: Ed Tanous <ed@tanous.net>
diff --git a/src/fru_utils.hpp b/src/fru_utils.hpp
index d6c2f6e..f6552a5 100644
--- a/src/fru_utils.hpp
+++ b/src/fru_utils.hpp
@@ -38,6 +38,7 @@
 using DeviceMap = boost::container::flat_map<int, std::vector<uint8_t>>;
 using BusMap = boost::container::flat_map<int, std::shared_ptr<DeviceMap>>;
 
+// NOLINTNEXTLINE(cppcoreguidelines-avoid-non-const-global-variables)
 inline BusMap busMap;
 
 enum class DecodeState