Blackfin arch: add support for Blackfin latest processor family BF51x

Signed-off-by: Bryan Wu <cooloney@kernel.org>

diff --git a/arch/blackfin/mach-common/pm.c b/arch/blackfin/mach-common/pm.c
index f774d8a..ee33a8a 100644
--- a/arch/blackfin/mach-common/pm.c
+++ b/arch/blackfin/mach-common/pm.c
@@ -83,9 +83,9 @@
 	bfin_pm_standby_restore();
 
 #if defined(CONFIG_BF54x) || defined(CONFIG_BF52x)  || defined(CONFIG_BF561) || \
-	defined(CONFIG_BF538) || defined(CONFIG_BF539)
+	defined(CONFIG_BF538) || defined(CONFIG_BF539) || defined(CONFIG_BF51x)
 	bfin_write_SIC_IWR0(IWR_DISABLE_ALL);
-#if defined(CONFIG_BF52x)
+#if defined(CONFIG_BF52x) || defined(CONFIG_BF51x)
 	/* BF52x system reset does not properly reset SIC_IWR1 which
 	 * will screw up the bootrom as it relies on MDMA0/1 waking it
 	 * up from IDLE instructions.  See this report for more info: