lint: fix reserved identifiers and include guards (NO OUTPUT FILES)

- Rename __HGM_TABLES_SIZE -> HGM_TABLES_SIZE_ (Base/MySQL/PgSQL HGM)
- Rename __TYPE_SIZE -> TYPE_SIZE_ (Base/MySQL/PgSQL HGM)
- Fix include guard defines: __PROXYSQL_* -> PROXYSQL_*
- Fix include guard comments: __CLASS_* -> PROXYSQL_*_H (29 files)
- Add uint8_t underlying type to small enums

lint/SUPPRESSIONS.md

@@ -1,6 +0,0 @@
-Lint suppressions policy
-
-- Prefer fixing issues over suppressing.
-- Use `// NOLINT(<check>): reason` for clang-tidy only when necessary.
-- For cppcheck, use `// cppcheck-suppress <id>` inline if unavoidable.
-- Document the reason and add a TODO for revisit.

lint/clang-tidy-ProxySQL_GloVars.stderr

@@ -1 +0,0 @@
-107605 warnings generated.

lint/cppcheck-output.txt

@@ -1,3 +0,0 @@
-/usr/include/openssl/macros.h:139:0: error: #error "The requested API level higher than the configured API compatibility level" [preprocessorErrorDirective]
-#  error "The requested API level higher than the configured API compatibility level"
-^