Empty ramdisk in boot.img

I have a copy of the boot.img from my HTC M8 one. I unpacked it and discovered that it is mostly empty directories and one binary "init" file. I was hoping to find an init.rc in there. Any ideas?

:/tmp/ramdisk$ cpio -idv < ramdisk.cpio 
apex
debug_ramdisk
dev
init
mnt
proc
sys
2690 blocks

:/tmp/ramdisk$ find
.
./init
./mnt
./ramdisk.cpio
./proc
./debug_ramdisk
./dev
./sys
./apex