feat(stm32mp15): disable OP-TEE shared memory

OP-TEE manages its own memory, and can open some areas through TZC400.
There is no need to configure this shared memory in TF-A.
Just assure that CFG_CORE_RESERVED_SHM=n for OP-TEE compilation.

Signed-off-by: Yann Gautier <yann.gautier@st.com>
Change-Id: Ib54acd60d9ec243d6ef9cc6b74937b4183d9ffa5
diff --git a/plat/st/stm32mp1/platform.mk b/plat/st/stm32mp1/platform.mk
index 194672e..ddc5289 100644
--- a/plat/st/stm32mp1/platform.mk
+++ b/plat/st/stm32mp1/platform.mk
@@ -62,7 +62,7 @@
 STM32_HEADER_VERSION_MINOR:=	0
 
 # Add OP-TEE reserved shared memory area in mapping
-STM32MP15_OPTEE_RSV_SHM	:=	1
+STM32MP15_OPTEE_RSV_SHM	:=	0
 $(eval $(call add_defines,STM32MP15_OPTEE_RSV_SHM))
 
 STM32MP_CRYPTO_ROM_LIB :=	1