patch 9.1.1287: quickfix code can be further improved

patch 9.1.1287: quickfix code can be further improved

Problem:  quickfix code can be further improved (after v9.1.1283)
Solution: slightly refactor quickfix.c (Hirohito Higashi)

- remove error message output
- adjust comments
- rename functions:
  - qf_init_quickfix_stack() --> qf_init_stack()
  - qf_resize_quickfix_stack() --> qf_resize_stack()
  - qf_resize_stack() --> qf_resize_stack_base()

Now qf_alloc_stack() can handle both quickfix/location lists.

closes: #17068

Signed-off-by: Hirohito Higashi <h.east.727@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>