FEATURE_IFCONFIG_BROADCAST_PLUS broken

[Matthias Reichl]

I just noticed that "ifconfig eth0 broadcast +" doesn't work, although
the FEATURE_IFCONFIG_BROADCAST_PLUS is enabled.

busybox 1.3.0 and 1.4.1 say "ifconfig: +: unknown host", current
svn says "ifconfig: bad address '+'".

I tested several older versions, this feature works fine up to 1.2.2.1
so I guess the bug must have sneaked in somewhere between October
and December last year.

so long,

Hias