initramfs: set $IFS to `hash -r` so newly build u-root commands are found
initramfs: set $IFS to `hash -r` so newly build u-root commands are found

This way, when a u-root command in /buildbin is built into /ubin, it will
be found in /ubin.

With this change, tinycore integration works very smoothly. To install a new command,
e.g. bash, one simply does
sudo -E tcz bash

and bash is ready to use.

Signed-off-by: Ronald G. Minnich <f569d0af9a3481c4007b95c7180d6c41009f2513@gmail.com>

GanShun/u-root,hugelgupf/u-root,GanShun/u-root,rminnich/u-root,hugelgupf/u-root,hugelgupf/u-root,rminnich/u-root,rminnich/u-root,u-root/u-root,u-root/u-root,GanShun/u-root,rminnich/u-root,u-root/u-root,hugelgupf/u-root