moved 'x11-misc/qtkeychain' to 'dev-libs/qtkeychain' to be aligned with ...

...gentoo tree

'qtkeychain' is in gentoo tree in category 'dev-libs'. The package in the overlay should align with it.

Best practice would be also to add 'dev-libs/qtkeychain::gentoo' to package.mask to avoid problems if a new package version is added to gentoo tree