Blackfin arch: add TWIx_REGBASE and SPIx_REGBASE to specific CPU header files, use the new REGBASE for board platform resources

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

diff --git a/include/asm-blackfin/mach-bf561/defBF561.h b/include/asm-blackfin/mach-bf561/defBF561.h
index 0f2dc6e..bf7dc4e 100644
--- a/include/asm-blackfin/mach-bf561/defBF561.h
+++ b/include/asm-blackfin/mach-bf561/defBF561.h
@@ -120,6 +120,7 @@
 #define UART_GCTL      	      	0xFFC00424	/* Global Control Register */
 
 /* SPI Controller (0xFFC00500 - 0xFFC005FF) */
+#define SPI0_REGBASE          		0xFFC00500
 #define SPI_CTL               		0xFFC00500	/* SPI Control Register */
 #define SPI_FLG               		0xFFC00504	/* SPI Flag register */
 #define SPI_STAT              		0xFFC00508	/* SPI Status register */