mm: allow access fastrpc total_dma_kb sysfs

Bug: 168084904
Test: boot
Signed-off-by: Martin Liu <liumartin@google.com>
Change-Id: I8a548fa667072f188b86d101b874a7cf8c9d5d79
diff --git a/mm/genfs_contexts b/mm/genfs_contexts
index 855a43f..57b26d4 100644
--- a/mm/genfs_contexts
+++ b/mm/genfs_contexts
@@ -1 +1,2 @@
 genfscon debugfs /page_owner                          u:object_r:debugfs_page_owner:s0
+genfscon sysfs /kernel/fastrpc/total_dma_kb            u:object_r:sysfs_fastrpc:s0