arm: dra7xx: Add dra7xx_evm build support

Adding the build support for dra7xx_evm.
Reusing omap5_evm.h config by moving it to omap5_common.h

Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: R Sricharan <r.sricharan@ti.com>
diff --git a/boards.cfg b/boards.cfg
index c117368..efe137d 100644
--- a/boards.cfg
+++ b/boards.cfg
@@ -285,6 +285,7 @@
 omap4_panda                  arm         armv7       panda               ti             omap4
 omap4_sdp4430                arm         armv7       sdp4430             ti             omap4
 omap5_evm                    arm         armv7       omap5_evm           ti		omap5
+dra7xx_evm		     arm	 armv7	     dra7xx		 ti	        omap5
 s5p_goni                     arm         armv7       goni                samsung        s5pc1xx
 smdkc100                     arm         armv7       smdkc100            samsung        s5pc1xx
 origen			     arm	 armv7	     origen		 samsung	exynos