Added method to convert state code into the human readable name.
It will be used in logging and error reporting.
(Bitbake rev: 9ec6379b27d210214d0b3f2e55962f721b7f5f51)
Signed-off-by: Ed Bartosh <ed.bartosh@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>