Userland: static vs non-static constexpr variables

Problem:
- `static` variables consume memory and sometimes are less
  optimizable.
- `static const` variables can be `constexpr`, usually.
- `static` function-local variables require an initialization check
  every time the function is run.

Solution:
- If a global `static` variable is only used in a single function then
  move it into the function and make it non-`static` and `constexpr`.
- Make all global `static` variables `constexpr` instead of `const`.
- Change function-local `static const[expr]` variables to be just
  `constexpr`.

Userland/Utilities/lspci.cpp

@@ -8,6 +8,7 @@
 #include <AK/JsonArray.h>
 #include <AK/JsonObject.h>
 #include <AK/String.h>
+#include <AK/StringView.h>
 #include <LibCore/ArgsParser.h>
 #include <LibCore/File.h>
 #include <LibPCIDB/Database.h>
@@ -16,8 +17,8 @@
 
 static bool flag_show_numerical = false;
 
-static const char* format_numerical = "{:04x}:{:02x}:{:02x}.{} {}: {}:{} (rev {:02x})";
-static const char* format_textual = "{:04x}:{:02x}:{:02x}.{} {}: {} {} (rev {:02x})";
+static constexpr StringView format_numerical = "{:04x}:{:02x}:{:02x}.{} {}: {}:{} (rev {:02x})";
+static constexpr StringView format_textual = "{:04x}:{:02x}:{:02x}.{} {}: {} {} (rev {:02x})";
 
 int main(int argc, char** argv)
 {
@@ -43,7 +44,7 @@ int main(int argc, char** argv)
     args_parser.add_option(flag_show_numerical, "Show numerical IDs", "numerical", 'n');
     args_parser.parse(argc, argv);
 
-    const char* format = flag_show_numerical ? format_numerical : format_textual;
+    const auto format = flag_show_numerical ? format_numerical : format_textual;
 
     RefPtr<PCIDB::Database> db;
     if (!flag_show_numerical) {