Apparently HEIF is common nowadays as it's the default image format for
new iOS [1].

[1] https://www.theverge.com/2017/9/19/16332192/apple-ios-11-heic-iphone-image-format

Also updates maintainership. Per https://archlinux.org/packages/community/x86_64/lximage-qt/, Jerome is no longer a maintainer.

archlinux/devtools!109 (comment 74475)

* Remove no longer needed -DCMAKE_INSTALL_LIBDIR=lib [1]. This package does not install to /usr/lib, anyway.

[1] https://git.archlinux.org/svntogit/packages.git/commit/trunk?h=packages/cmake&id=26b053e768072197c4ce326fd620f5ab01d74407

* Use HTTPS in `url`
* Expand `depends` - include libraries that are directly linked, following
  "no transitive dependency" movement
  https://github.com/lxqt/lximage-qt/blob/0.14.1/src/CMakeLists.txt#L94
  (libx11 is also directly linked; I assume it will still be brought in by
   libxfixes in near future)
* Use the LXQt GitHub organization in `source`

FTR, commands used to change arch=() and then verify the changes:

$ sed -Ei "/^arch=/{s/ *?['\"]?i686['\"]? *?//;s/ *$//}" */*/PKGBUILD*

$ grep -r i686 * | grep arch= | grep -v repos

$ svn diff | grep -A 1 ^-[^-] | grep -v -- -- | cut -c2- |
  while IFS=$'\n' read -r l1; IFS=$'\n' read -r l2; do
    echo "$l1 -> $l2"
  done | sort -u