Add toybox seq.

Bug: https://issuetracker.google.com/129992021
Test: builds
Change-Id: Icb737dcba0928cb1ab39620e4bc71e64539c2a71
diff --git a/path/linux-x86/seq b/path/linux-x86/seq
new file mode 120000
index 0000000..c6b4b1f
--- /dev/null
+++ b/path/linux-x86/seq
@@ -0,0 +1 @@
+../../linux-x86/bin/toybox
\ No newline at end of file