[packages] wget: Fix installation and cleanup package makefile (#6990)

[packages] wget: Fix installation and cleanup package makefile (#6990)

* wget package binary installed at /usr/bin/wget-ssl
* wget-nossl package binary installed at /usr/bin/wget-nossl
* allows both packages to co-exist without conflict
* busybox symlink is replaced with symlink to newest package binary
* symlink is restored when removing package with the following preference:
	1. /usr/bin/wget-ssl or /usr/bin/wget-nossl
	2. /bin/busybox

git-svn-id: svn://svn.openwrt.org/openwrt/packages@20583 3c298f89-4303-0410-b956-a3cf2f4a3e73