When using '-cpu help' the list of CPUID features is grouped according
to the internal low level CPUID grouping. The data printed results in
very long lines too.

This combines to make it hard for users to read the output and identify
if QEMU knows about the feature they wish to use.

This change gets rid of the grouping of features and treats all flags as
single list. The list is sorted into alphabetical order and the printing
with line wrapping at the 77th column.
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>
Message-Id: <20180606165527.17365-4-berrange@redhat.com>
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>