Make clang-tidy changes

clang-tidy has a number of checks it recommends.  These checks are
documented in the next commit, but make the code pass our coding
standard.

Tested:
Minor changes made by the robot.

Signed-off-by: Ed Tanous <edtanous@google.com>
Change-Id: I6cfaab92211af9c4c1eccd981ba9fe7b8c523457
diff --git a/include/fru_utils.hpp b/include/fru_utils.hpp
index ebb2b19..e50b580 100644
--- a/include/fru_utils.hpp
+++ b/include/fru_utils.hpp
@@ -17,6 +17,7 @@
 
 #pragma once
 #include "fru_reader.hpp"
+
 #include <boost/container/flat_map.hpp>
 
 #include <cstdint>
@@ -94,7 +95,7 @@
 char sixBitToChar(uint8_t val);
 
 /* 0xd - 0xf are reserved values, but not fatal; use a placeholder char. */
-const char bcdHighChars[] = {
+constexpr std::array<char, 6> bcdHighChars = {
     ' ', '-', '.', 'X', 'X', 'X',
 };