gnu: Remove linux-libre 6.7.
* gnu/packages/linux.scm (linux-libre-6.7-version, linux-libre-6.7-gnu-revision,
deblob-scripts-6.7, linux-libre-6.7-pristine-source, linux-libre-6.7-source,
linux-libre-headers-6.7, linux-libre-6.7): Remove variables.
* gnu/packages/aux-files/linux-libre/6.7-arm.conf,
gnu/packages/aux-files/linux-libre/6.7-arm64.conf,
gnu/packages/aux-files/linux-libre/6.7-i686.conf,
gnu/packages/aux-files/linux-libre/6.7-x86_64.conf: Delete files.
* Makefile.am (AUX_FILES): Remove aforementioned .conf files.
Change-Id: Ic69a65e1fbfa59d893e85d26950f33195ea9fbe1
Signed-off-by: Leo Famulari <leo@famulari.name>