Name
fence_context_alloc — 
  allocate an array of fence contexts
 
Synopsis
| unsigned fence_context_alloc ( | unsigned num ); | 
 
Arguments
- num
- 
     [in]	amount of contexts to allocate
     
Description
   This function will return the first index of the number of fences allocated.
   The fence context is used for setting fence->context to a unique number.