device_as_map: Remove expect(s)
device_as_map: Remove expect(s)

Remove the possiblity of panicing the daemon on bad data from
udev.

Signed-off-by: Tony Asleson <1ef2d381aa56d512126ddaacc29e68136e4fdf55@redhat.com>

stratis-storage/stratisd,trgill/stratisd,stratis-storage/stratisd,stratis-storage/stratisd,mulkieran/stratisd,trgill/stratisd,mulkieran/stratisd