Cleanup the code for TBBR CoT descriptors

CoT used for BL1 and BL2 are moved to tbbr_cot_bl1.c
and tbbr_cot_bl2.c respectively.
Common CoT used across BL1 and BL2 are moved to
tbbr_cot_common.c.

Signed-off-by: Manish V Badarkhe <Manish.Badarkhe@arm.com>
Change-Id: I2252ac8a6960b3431bcaafdb3ea4fb2d01b79cf5
diff --git a/plat/brcm/board/common/board_common.mk b/plat/brcm/board/common/board_common.mk
index 1795ce7..808a107 100644
--- a/plat/brcm/board/common/board_common.mk
+++ b/plat/brcm/board/common/board_common.mk
@@ -213,7 +213,8 @@
 AUTH_SOURCES	+= 	drivers/auth/auth_mod.c \
 			drivers/auth/crypto_mod.c \
 			drivers/auth/img_parser_mod.c \
-			drivers/auth/tbbr/tbbr_cot.c
+			drivers/auth/tbbr/tbbr_cot_common.c \
+			drivers/auth/tbbr/tbbr_cot_bl2.c
 
 BL2_SOURCES	+=	${AUTH_SOURCES}