build_macros.mk: include assert and define loop macros

Loop macros make it easier for developers to include new variables to
assert or define and also help code code readability on makefiles.

Change-Id: I0d21d6e67b3eca8976c4d856ac8ccc02c8bb5ffa
Signed-off-by: Leonardo Sandoval <leonardo.sandoval@linaro.org>
diff --git a/drivers/measured_boot/measured_boot.mk b/drivers/measured_boot/measured_boot.mk
index fc005d5..b7aa48b 100644
--- a/drivers/measured_boot/measured_boot.mk
+++ b/drivers/measured_boot/measured_boot.mk
@@ -25,10 +25,13 @@
 EVENT_LOG_SIZE			:= 1024
 
 # Set definitions for mbed TLS library and Measured Boot driver
-$(eval $(call add_define,MBEDTLS_MD_ID))
-$(eval $(call add_define,TPM_ALG_ID))
-$(eval $(call add_define,TCG_DIGEST_SIZE))
-$(eval $(call add_define,EVENT_LOG_SIZE))
+$(eval $(call add_defines,\
+    $(sort \
+        MBEDTLS_MD_ID \
+        TPM_ALG_ID \
+        TCG_DIGEST_SIZE \
+        EVENT_LOG_SIZE \
+)))
 
 ifeq (${HASH_ALG}, sha256)
 ifneq (${TPM_HASH_ALG}, sha256)