busybox: enable find mtime support by default

busybox: enable find mtime support by default

busybox binary in openwrt neither supports stat nor find
mtime. This patch adds find mtime support by default.

I've compared ipk size for three different targets
(ar71xx, brcm2708, x86):

209908 Okt 16 13:48 busybox_1.23.2-3_ar71xx.ipk-0before
210031 Okt 16 16:47 busybox_1.23.2-3_ar71xx.ipk-1after
difference: +123 Byte

223519 Okt 16 13:06 busybox_1.23.2-3_brcm2708.ipk-0before
223720 Okt 16 13:53 busybox_1.23.2-3_brcm2708.ipk-1after
difference: +201 Byte

221477 Okt 16 13:47 busybox_1.23.2-3_x86_64.ipk-0before
221622 Okt 16 13:52 busybox_1.23.2-3_x86_64.ipk-1after
difference: +145 Byte

Signed-off-by: Dirk Brenken <dirk@brenken.org>
git-svn-id: svn://svn.openwrt.org/openwrt/trunk@47362 3c298f89-4303-0410-b956-a3cf2f4a3e73