sdcard_image-rpi.bbclass: remove redundant IMAGEDATESTAMP

The IMAGE_NAME variable already contains the date and time so it is
redundant to also include the date again with IMAGEDATESTAMP
when writing to image-version-info in the boot partition.

Signed-off-by: Jonathan Liu <net147@gmail.com>

classes/sdcard_image-rpi.bbclass

@@ -71,10 +71,6 @@ SDIMG = "${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.rootfs.rpi-sdimg"
 # Additional files and/or directories to be copied into the vfat partition from the IMAGE_ROOTFS.
 FATPAYLOAD ?= ""
 
-IMAGEDATESTAMP = "${@time.strftime('%Y.%m.%d',time.gmtime())}"
-IMAGE_CMD_rpi-sdimg[vardepsexclude] += "IMAGEDATESTAMP"
-IMAGE_CMD_rpi-sdimg[vardepsexclude] += "DATETIME"
-
 IMAGE_CMD_rpi-sdimg () {
 
 	# Align partitions
@@ -143,8 +139,8 @@ IMAGE_CMD_rpi-sdimg () {
 	fi
 
 	# Add stamp file
-	echo "${IMAGE_NAME}-${IMAGEDATESTAMP}" > ${WORKDIR}/image-version-info
-	mcopy -i ${WORKDIR}/boot.img -v ${WORKDIR}//image-version-info ::
+	echo "${IMAGE_NAME}" > ${WORKDIR}/image-version-info
+	mcopy -i ${WORKDIR}/boot.img -v ${WORKDIR}/image-version-info ::
 
 	# Burn Partitions
 	dd if=${WORKDIR}/boot.img of=${SDIMG} conv=notrunc seek=1 bs=$(expr ${IMAGE_ROOTFS_ALIGNMENT} \* 1024) && sync && sync