test: Clean up Automake integration of tests

Signed-off-by: Jacques de Laval <jacques@de-laval.se>

test/test_root/.gitignore

@@ -1,4 +1,25 @@
-/bin
+/bin/busybox-x86_64
+/bin/cat
+/bin/cp
+/bin/date
+/bin/echo
+/bin/env
+/bin/find
+/bin/initctl
+/bin/kill
+/bin/ls
+/bin/mkdir
+/bin/mkfifo
+/bin/mknod
+/bin/mount
+/bin/pgrep
+/bin/printf
+/bin/ps
+/bin/rm
+/bin/sh
+/bin/sleep
+/bin/top
+/bin/touch
 /dev
 /etc
 /lib64