gralloc: Allow unmapping concurrent handles

If we allow registering those buffers, we need to let them go, too

Change-Id: I6c2dc862e1e783e2b0d3c7d37d60ebe2290173fa

exynos4/hal/libgralloc_ump/gralloc_module.cpp

@@ -318,8 +318,6 @@ static int gralloc_unregister_buffer(gralloc_module_t const* module, buffer_hand
     ALOGE_IF(hnd->lockState & private_handle_t::LOCK_STATE_READ_MASK,
             "[unregister] handle %p still locked (state=%08x)", hnd, hnd->lockState);
 
-    /* never unmap buffers that were created in this process */
-    if (hnd->pid != getpid()) {
     pthread_mutex_lock(&s_map_lock);
     if (hnd->flags & private_handle_t::PRIV_FLAGS_USES_UMP) {
         ump_mapped_pointer_release((ump_handle)hnd->ump_mem_handle);
@@ -353,7 +351,6 @@ static int gralloc_unregister_buffer(gralloc_module_t const* module, buffer_hand
     }
 
     pthread_mutex_unlock(&s_map_lock);
-    }
 
     return 0;
 }