TABLE::mark_virtual_col() was polluting table->vcol_set
and that confused the following mark_virtual_col()

make it to work when read_set == vcol_set, that is, when
the caller wants to get a one complete bitmap of all fields
a particular vcol depends on.

it was done only in some access methods, not in all,
so the caller had to update_virtual_fields anyway.

In spatial indexes there can be only one keyseg.
Make it explicit in the code, don't pretend that this can work
with the arbitrary number of keysegs.

and FIELDFLAG_xxx constants

prefer x->field over table->field[x->field->field_index]

only use my_print_error when the error message is not
ER(error_code)

the stage is changed from 'old_stage' to 'new_stage',
not the other way around

and partition_info::set_show_version_string - they were
already broken and impossible to maintain

unused freshly initialized record should be trashed
with TRASH_ALLOC, not TRASH_FREE

remove redundant method

also, return different values for different errors in my_addr_resolve()

MDEV-11075: Power - runtime detection of optimized instructions

Signed-off-by: Daniel Black <daniel.black@au.ibm.com>

        The weird logic of json_contains was implemented.