Bug#916958: user-mode-linux build depends on linux-source-4.17 but it is not installable

[Adrian Bunk]

Source: user-mode-linux
Version: 4.17-1um-1
Severity: serious
Tags: ftbfs

The following packages have unmet dependencies:
 builddeps:user-mode-linux : Depends: linux-source-4.17 but it is not 
installable