CFG_TEE_CORE_LOG_LEVEL not fixed anymore

Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
Reviewed-by: Joakim Bech <joakim.bech@linaro.org>
Signed-off-by: Pascal Brand <pascal.brand@st.com>
diff --git a/common.mk b/common.mk
index 7d146ae..af7e801 100644
--- a/common.mk
+++ b/common.mk
@@ -15,6 +15,8 @@
 OPTEE_TEST_PATH			?= $(ROOT)/optee_test
 OPTEE_TEST_OUT_PATH 		?= $(ROOT)/optee_test/out
 
+CFG_TEE_CORE_LOG_LEVEL		?= 3
+
 CCACHE ?= $(shell which ccache) # Don't remove this comment (space is needed)
 
 
@@ -184,7 +186,7 @@
 	CROSS_COMPILE_core=$(CROSS_COMPILE_S_KERNEL) \
 	CROSS_COMPILE_ta_arm64=$(AARCH64_CROSS_COMPILE) \
 	CROSS_COMPILE_ta_arm32=$(AARCH32_CROSS_COMPILE) \
-	CFG_TEE_CORE_LOG_LEVEL=3 \
+	CFG_TEE_CORE_LOG_LEVEL=$(CFG_TEE_CORE_LOG_LEVEL) \
 	DEBUG=$(DEBUG)
 
 optee-os-common: