[PROBLEM] Increase network buffer

[Pihkal]

@Koenkk:

20971520 crashed xbmc while streaming with the icefilm-addon.
But i'm using a 128/128 split,so it's not that unexpected.

Code:

[ 1138.221435] Out of memory: Kill process 2332 (xbmc.bin) score 628 or sacrifice child
[ 1138.221451] Killed process 2332 (xbmc.bin) total-vm:369280kB, anon-rss:76688kB, file-rss:568kB

Changing the split back to 156/100 and re-trying...

This also crashed xbmc,this time while streaming 1080p content from youtube.
Same "out of memory" message in dmesg.

Now trying Koenkk's suggested value.