Optimization for MDEV-10411 Providing compatibility for basic PL/SQL constructs

When processing an SP body:

CREATE PROCEDURE p1 (parameters)
AS [ declarations ]
BEGIN statements
[ EXCEPTION exceptions ]
END;

the parser generates two "jump" instructions:
- from the end of "declarations" to the beginning of EXCEPTION
- from the end of EXCEPTION to "statements"

These jumps are useless if EXCEPTION does not exist.
This patch makes sure that these two "jump" instructions are
generated only if EXCEPTION really exists.

mysql-test/suite/compat/oracle/r/sp-code.result

@@ -21,7 +21,7 @@ END;
 /
 SHOW PROCEDURE CODE p1;
 Pos	Instruction
-0	jump 3
+0	jump 2
 CALL p1;
 DROP PROCEDURE p1;
 # No HANDLER declarations, no code, some exceptions
@@ -133,10 +133,9 @@ SHOW PROCEDURE CODE p1;
 Pos	Instruction
 0	hpush_jump 3 1 EXIT
 1	set v@0 123
-2	hreturn 0 5
+2	hreturn 0 4
 3	set v@0 223
-4	jump 5
-5	hpop 1
+4	hpop 1
 set @v= 10;
 CALL p1(@v);
 SELECT @v;