Fix sha512sum file generation
Fix sha512sum file generation

Change sha512sum command line so that it does not include subdirectory
paths with the filename in the generated file, as that makes it harder
to check the sha512sum later via the --check option.

Signed-off-by: Simo Sorce <65f99581a93cf30dafc32b5c178edc6b0294a07f@redhat.com>

pythongssapi/python-gssapi,pythongssapi/python-gssapi,pythongssapi/python-gssapi