MDEV-33281 Implement optimizer hints

This commit introduces:
    - the infrastructure for optimizer hints;
    - hints for join buffering: BNL(), NO_BNL(), BKA(), NO_BKA();
    - NO_ICP() hint for disabling index condition pushdown;
    - MRR(), MO_MRR() hint for multi-range reads control;
    - NO_RANGE_OPTIMIZATION() for disabling range optimization;
    - QB_NAME() for assigning names for query blocks.

sql/opt_hints_parser.h

@@ -23,6 +23,19 @@
 #include "sql_list.h"
 #include "simple_parser.h"
 
+class st_select_lex;
+
+/**
+  Environment data for the name resolution phase
+*/
+struct Parse_context {
+  THD * const thd;              ///< Current thread handler
+  MEM_ROOT *mem_root;           ///< Current MEM_ROOT
+  st_select_lex * select;       ///< Current SELECT_LEX object
+
+  Parse_context(THD *thd, st_select_lex *select);
+};
+
 
 class Optimizer_hint_tokenizer: public Extended_string_tokenizer
 {
@@ -513,7 +526,6 @@ private:
     using OR2::OR2;
   };
 
-
   // table_level_hint ::= table_level_hint_type ( table_level_hint_body )
   class Table_level_hint: public AND4<PARSER,
                                       Table_level_hint_type,
@@ -523,6 +535,8 @@ private:
   {
   public:
     using AND4::AND4;
+
+    bool resolve(Parse_context *pc) const;
   };
 
 
@@ -545,6 +559,8 @@ private:
   {
   public:
     using AND4::AND4;
+    
+    bool resolve(Parse_context *pc) const;
   };
 
 
@@ -557,6 +573,8 @@ private:
   {
   public:
     using AND4::AND4;
+
+    bool resolve(Parse_context *pc) const;
   };
 
 
@@ -572,6 +590,7 @@ private:
   {
   public:
     using OR3::OR3;
+
   };
 
 
@@ -592,6 +611,8 @@ public:
   {
   public:
     using LIST::LIST;
+    
+    bool resolve(Parse_context *pc);
   };
 
   /*