image: add new "copro" image type

Define new image type for coprocessor images.
It is used in FIT to identify the files loaded
with remoteproc command (elf or bin).

Signed-off-by: Loic Pallardy <loic.pallardy@st.com>
Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/common/image.c b/common/image.c
index 645584b..179eef0 100644
--- a/common/image.c
+++ b/common/image.c
@@ -176,6 +176,7 @@
 	{       IH_TYPE_PMMC,        "pmmc",        "TI Power Management Micro-Controller Firmware",},
 	{	IH_TYPE_STM32IMAGE, "stm32image", "STMicroelectronics STM32 Image" },
 	{	IH_TYPE_MTKIMAGE,   "mtk_image",   "MediaTek BootROM loadable Image" },
+	{	IH_TYPE_COPRO, "copro", "Coprocessor Image"},
 	{	-1,		    "",		  "",			},
 };