hw/s390x/ccw: Replace basename() with g_path_get_basename()

hw/s390x/ccw: Replace basename() with g_path_get_basename()

g_path_get_basename() is a portable utility function that has the
advantage of not modifying the string argument, so it should be
preferred over basename().

And also to avoid potential compile breakage with the Musl C library
similar to [1], replace basename() with g_path_get_basename().

[1]: https://lore.kernel.org/all/20231212010228.2701544-1-raj.khem@gmail.com/

Suggested-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
Message-ID: <20231221171921.57784-2-zhao1.liu@linux.intel.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>