When finit calls out to external tools, like `ifup $IFACE`, that tool in
turn may use other external tools. On systems with BusyBox our calling
`ifup $IFACE` will result in BusyBox casting a magic spell: if $SHELL is
unset it goes looking in the file /etc/passwd for the shell of $USER
which may not be set to a Bourne compatible UNIX shell, so commands like
`ip link ...` or `run-parts ...` will fail hard.
This patch adds SHELL=/bin/sh as a sane early default.
Signed-off-by: Joachim Nilsson <troglobit@gmail.com>
Joachim Nilsson
a50bfc016e