gitignore: Ignore all cscope files

Change-Id: I91dd5df23491d9377bcbbc529b08529818f06285
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
diff --git a/.gitignore b/.gitignore
index e87701d..af90333 100644
--- a/.gitignore
+++ b/.gitignore
@@ -49,7 +49,7 @@
 arm-openbmc-linux-gnueabi-libtool
 /mboxd
 mboxctl
-cscope.out
+/cscope.*
 /test/*.o
 
 # Autotools test infrastructure