chore: add encrypt_fw to gitignore

Add tools/encrypt_fw/encrypt_fw & tools/encrypt_fw/encrypt_fw.exe to
.gitignore file, to avoid git listing those binary files.

Signed-off-by: Yann Gautier <yann.gautier@foss.st.com>
Change-Id: I2f4ddbe1c11848513fe20f7c8b448a041988cc4f
1 file changed