.gitignore: add compile

Yet another artefact from the autotools buildsystem.
Signed-off-by: Emil Velikov <emil.l.velikov@gmail.com>
Reviewed-by: Aaron Plattner <aplattner@nvidia.com>
Signed-off-by: Aaron Plattner <aplattner@nvidia.com>

.gitignore

@@ -10,6 +10,7 @@ config.log
 config.status
 config.sub
 configure
+compile
 depcomp
 doc/html-out
 install-sh