bletiny - Fix for descriptor discovery.
bletiny - Fix for descriptor discovery.

The NimBLE host was changed to use the characteristic value handle
everywhere (whereas it used to use the definition handle in a few
places).  bletiny was never updated to account for this change.

andrzej-kaczmarek/incubator-mynewt-core,andrzej-kaczmarek/incubator-mynewt-core,IMGJulian/incubator-mynewt-core,IMGJulian/incubator-mynewt-core,andrzej-kaczmarek/incubator-mynewt-core,IMGJulian/incubator-mynewt-core,IMGJulian/incubator-mynewt-core,mlaz/mynewt-core,mlaz/mynewt-core,wes3/incubator-mynewt-core,wes3/incubator-mynewt-core,andrzej-kaczmarek/apache-mynewt-core,mlaz/mynewt-core,andrzej-kaczmarek/incubator-mynewt-core,IMGJulian/incubator-mynewt-core,wes3/incubator-mynewt-core,mlaz/mynewt-core,andrzej-kaczmarek/apache-mynewt-core,andrzej-kaczmarek/incubator-mynewt-core,mlaz/mynewt-core,wes3/incubator-mynewt-core,wes3/incubator-mynewt-core,andrzej-kaczmarek/apache-mynewt-core,andrzej-kaczmarek/apache-mynewt-core