Merge bitcoin/bitcoin#21932: [0.21] depends: update Qt 5.9 source url

deff4e763e11f92e5cb7732cace7239fead4fba8 depends: update Qt 5.9 source url (Kittywhiskers Van Gogh)

Pull request description:

  ## Expected Behavior

  Running `make` in the depends directory should result in the successful building of host platform dependencies

  ## Actual Behavior

  `make` terminates as `qt.mk` points to (now) outdated URL path for Qt 5.9 sources, returning error 404

  ## Remedy

  Update `qt.mk` to point to updated source location as Qt has relocated them

ACKs for top commit:
  RandyMcMillan:
    tACK deff4e7
  hebasto:
    ACK deff4e763e11f92e5cb7732cace7239fead4fba8, I have verified the new link, and checked that old one is unavailable:
  jarolrod:
    tACK deff4e763e11f92e5cb7732cace7239fead4fba8

Tree-SHA512: d5b11a678c871a87e6884a35641178ee349728ead51da06018953be36aab5a30aef9c80b549da49802e87903eb0b7836cc343301325bd8c505cb4246f6752505

Author: laanwj

depends/packages/qt.mk

@@ -1,6 +1,6 @@
 PACKAGE=qt
 $(package)_version=5.9.8
-$(package)_download_path=https://download.qt.io/official_releases/qt/5.9/$($(package)_version)/submodules
+$(package)_download_path=https://download.qt.io/archive/qt/5.9/$($(package)_version)/submodules
 $(package)_suffix=opensource-src-$($(package)_version).tar.xz
 $(package)_file_name=qtbase-$($(package)_suffix)
 $(package)_sha256_hash=9b9dec1f67df1f94bce2955c5604de992d529dde72050239154c56352da0907d