Fixes set_learning_phase in CNTK
Was getting an error when calling
```
K.set_learning_phase(0)
```
@@ -57,7 +57,7 @@ def set_learning_phase(value):
raise ValueError('CNTK Backend: Set learning phase '
'with value %s is not supported, '
'expected 0 or 1.' % value)
- v = np.float32([value])
+ v = np.asarray(value)
_LEARNING_PHASE.value = v
