There are no /dev/dma_heap/system and /dev/dma_heap/system-uncached.
It's because below commit remove CONFIG_DMABUF_HEAPS_SYSTEM.Here add it back.
245777a0 Jindong Yue MA-18983-3 defconfig: Sync defconfig after kernel merge

Change-Id: I38259bebf177ebe711b6a543dabb6c952232e241
Signed-off-by: Jessie Hao <juan.hao@nxp.com>