docs: fix 23 typos in source comments

[Avicennasis]

Summary

Fixes 23 spelling and grammar typos in source-code comments across six files
in src/. No code, identifiers, or behaviour are changed - every hunk is
inside a /* */ or // comment.

Cited fixes (21)

• src/system/vreq.c: privledged -> privileged; base respons on -> base response on
• src/lib/list_files.c: funciton -> function; lenght -> length;
  unecessary -> unnecessary; succes and nil pointer -> success and nil pointer;
  If qualifiy is set -> If qualify is set (now matches the real qualify parameter)
• src/vfd/vfd_dcb.c: funcitons -> functions (x2); This funciton is -> This function is
• src/lib/filesys.c: rname() -> rename(); Convenience funcitons -> Convenience functions;
  soruce file des -> source file des; unditionally free -> unconditionally free
• src/lib/id_mgr.c: finshed -> finished; ititialise -> initialise (en-GB spelling kept,
  matching the rest of the repo); A return of -1 indicated an error -> indicates;
  offset into bit poool -> offset into bit pool (x3)
• src/lib/jw_xapi.c: 'primatives' -> 'primitives'

Additionally noticed (2, not in the original report)

• src/vfd/vfd_dcb.c lines 98 and 216: arbitors -> arbiters in two comments.
  The repo already spells it arbiters in src/vfd/qos.c, so this is an internal
  inconsistency rather than a preference.

Deliberately left alone

• simpe_atomic_swap, waist_cycles, waist_time, t_usefull in
  src/support/dpdk_app/ifrate.h and src/support/dpdk_app/utils.h are real
  identifiers; renaming them would be an API change, so they are untouched.
• "The calling programme" in src/vfd/vfd_dcb.c and src/vfd/sriov.c is left as
  written: the repo uses "programme"/"programmes" consistently (4 occurrences, no
  American "program" anywhere) alongside "initialise"/"recognised", so it is the
  author's spelling, not a typo.
• Not changed here, but worth a look: src/lib/jw_xapi.c
jwx_get_value_as_str() appears to be missing a break; after the
  case JWFMT_FLOAT: branch (line 75), so a float format falls through to
  JWFMT_HEX. That is a behavioural fix and is intentionally not part of
  this documentation-only PR.