tools: Add stm32image tool into TF-A

This tools adds a specific header to ST TF-A binary.
This header is used by STM32MP1 ROM code to check the bootloader.

Signed-off-by: Yann Gautier <yann.gautier@st.com>
Signed-off-by: Lionel Debieve <lionel.debieve@st.com>
diff --git a/.gitignore b/.gitignore
index 7f8642e..78da669 100644
--- a/.gitignore
+++ b/.gitignore
@@ -19,6 +19,9 @@
 tools/cert_create/cert_create
 tools/cert_create/cert_create.exe
 tools/doimage/doimage
+tools/stm32image/*.o
+tools/stm32image/stm32image
+tools/stm32image/stm32image.exe
 
 # GNU GLOBAL files
 GPATH