ARM: DRA7xx: Enable FIT for hs platforms

Use a single defconfig for all DRA7xx hs platforms by enabling FIT and delete
the platform specific defconfigs.

Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
diff --git a/board/ti/dra7xx/MAINTAINERS b/board/ti/dra7xx/MAINTAINERS
index 907cb13..46b6e82 100644
--- a/board/ti/dra7xx/MAINTAINERS
+++ b/board/ti/dra7xx/MAINTAINERS
@@ -4,3 +4,4 @@
 F:	board/ti/dra7xx/
 F:	include/configs/dra7xx_evm.h
 F:	configs/dra7xx_evm_defconfig
+F:	configs/dra7xx_hs_evm_defconfig