The build-without-default-features job is running quite long and sometimes
already hits the 1h time limit. Exclude some targets which do not provide
additional test coverage here (since we e.g. also already test other targets
of the same type, just with different endianess, or a 64-bit superset) to
avoid that we hit the timeout here so easily.

Message-Id: <20210126172345.15947-1-thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Wainer dos Santos Moschetta <wainersm@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>