Add files/ironic-inspector* to .gitignore

When ironic-inspector is enabled through devstack, these two files
are created which needs to be masked.

Change-Id: I7a3db6fd6197da20cca1e938727d54195957ac18
Closes-Bug: #1690105
diff --git a/.gitignore b/.gitignore
index d1781bc..7967e14 100644
--- a/.gitignore
+++ b/.gitignore
@@ -23,6 +23,7 @@
 files/pip-*
 files/get-pip.py*
 files/ir-deploy*
+files/ironic-inspector*
 local.conf
 local.sh
 localrc