Blackfin arch: move hard coded pin_req to board file

Remove some sort of bloaty code, try to get these pin_req arrays built at compile-time

 - move this static things to the blackfin board file
 - add pin_req array to struct bfin5xx_spi_master
 - tested on BF537/BF548 with SPI flash

Signed-off-by: Bryan Wu <bryan.wu@analog.com>

diff --git a/arch/blackfin/mach-bf561/boards/cm_bf561.c b/arch/blackfin/mach-bf561/boards/cm_bf561.c
index 97aeb43..9e46b52 100644
--- a/arch/blackfin/mach-bf561/boards/cm_bf561.c
+++ b/arch/blackfin/mach-bf561/boards/cm_bf561.c
@@ -38,6 +38,7 @@
 #include <linux/irq.h>
 #include <asm/dma.h>
 #include <asm/bfin5xx_spi.h>
+#include <asm/portmux.h>
 
 /*
  * Name the Board for the /proc/cpuinfo
@@ -182,6 +183,7 @@
 static struct bfin5xx_spi_master bfin_spi0_info = {
 	.num_chipselect = 8,
 	.enable_dma = 1,  /* master has the ability to do dma transfer */
+	.pin_req = {P_SPI0_SCK, P_SPI0_MISO, P_SPI0_MOSI, 0},
 };
 
 static struct platform_device bfin_spi0_device = {