DMAENGINE: ste_dma40: only write phy channel config first time

We only need to write the configuration to a physical channel if
it is free, else it is already written.

Signed-off-by: Jonas Aaberg <jonas.aberg@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

drivers/dma/ste_dma40_ll.h

@@ -13,6 +13,9 @@
 #define D40_DREG_PCDELTA	(8 * 4)
 #define D40_LLI_ALIGN		16 /* LLI alignment must be 16 bytes. */
 
+#define D40_LCPA_CHAN_SIZE 32
+#define D40_LCPA_CHAN_DST_DELTA 16
+
 #define D40_TYPE_TO_GROUP(type) (type / 16)
 #define D40_TYPE_TO_EVENT(type) (type % 16)