net-libs/libproxy: update dependencies
KDE module dependency changed from linked (against Qt/KDE) to runtime, which uses kreadconfig/kreadconfig5.
This change was introduced in https://github.com/libproxy/libproxy/commit/
bd9bf72e15107e6c6133b438c700dd42d79c9d60.
Thanks to Arfrever for shedding light on this in bug #574046.
Since https://github.com/libproxy/libproxy/commit/
00975fa11220af11398f9d89ee2ee0cf17c655d2 libproxy supports webkit:4.
Thanks-to: Arfrever Frehtes Taifersar Arahesis <arfrever.fta@gmail.com>
Gentoo-Bug: 574046