build(st): update ST version

Update ST version to v2.0.

Signed-off-by: Yann Gautier <yann.gautier@st.com>
Change-Id: I24eea59f5f2cf1b7fbc2ca1809449ec2626de40a
Reviewed-on: https://gerrit.st.com/c/mpu/oe/st/tf-a/+/388484
ACI: CITOOLS <MDG-smet-aci-reviews@list.st.com>
Tested-by: Yann GAUTIER <yann.gautier@foss.st.com>
Domain-Review: Sebastien PASDELOUP <sebastien.pasdeloup-ext@st.com>
Reviewed-by: Yann GAUTIER <yann.gautier@foss.st.com>
ACI: CIBUILD <MDG-smet-aci-builds@list.st.com>
Reviewed-by: Sebastien PASDELOUP <sebastien.pasdeloup-ext@st.com>

Author: Yann-lms

plat/st/common/common.mk

@@ -11,7 +11,7 @@ STM32MP_RECONFIGURE_CONSOLE ?=	0
 STM32MP_UART_BAUDRATE	?=	115200
 
 # Add specific ST version
-ST_VERSION 		:=	r1.1
+ST_VERSION 		:=	r2.0
 ST_GIT_SHA1		:=	$(shell git rev-parse --short=8 HEAD 2>/dev/null)
 VERSION_STRING		:=	v${VERSION_MAJOR}.${VERSION_MINOR}-${PLAT}-${ST_VERSION}(${BUILD_TYPE}):${BUILD_STRING}(${ST_GIT_SHA1})