Suppress some clang-tidy errors

Split the .clang-tidy check lists out over multiple lines to improve
readability.

Suppress `misc-non-private-member-variables-in-classes` as the code
currently contains many instances that fail this check.

Drop `constexpr` from `LoopControlLoopCountINTELMask` after clang
started diagnosing this with b364535 ("[Clang] Diagnose
ill-formed constant expression when setting ...", 2022-07-28).
Removing `constexpr` is just a workaround, the long term fix would be
to upstream the new enum value to `spirv.hpp`.

Original commit:
KhronosGroup/SPIRV-LLVM-Translator@c5b29f2

Author: svenvh

.clang-tidy

@@ -1,22 +1,5 @@
-Checks: |
-  -*,
-  clang-diagnostic-*,
-  llvm-*,
-  -llvm-header-guard,
-  misc-*,
-  -misc-const-correctness,
-  -misc-no-recursion,
-  -misc-non-private-member-variables-in-classes,
-  -misc-unused-parameters,
-  readability-identifier-naming
-WarningsAsErrors: |
-  llvm-*,
-  -llvm-header-guard,
-  misc-*,
-  -misc-no-recursion,
-  -misc-non-private-member-variables-in-classes,
-  -misc-unused-parameters,
-  readability-identifier-naming
+Checks: '-*,clang-diagnostic-*,llvm-*,misc-*,-misc-unused-parameters,-misc-non-private-member-variables-in-classes,-misc-no-recursion,readability-identifier-naming'
+WarningsAsErrors: 'llvm-*,misc-*,-misc-no-recursion,-misc-unused-parameters,readability-identifier-naming,-llvm-header-guard'
 CheckOptions:
   - key:             readability-identifier-naming.ClassCase
     value:           CamelCase
@@ -42,5 +25,3 @@ CheckOptions:
     value:           1
   - key:             modernize-use-default-member-init.UseAssignment
     value:           1
-  - key:             llvm-namespace-comment.ShortNamespaceLines
-    value:           '25'