Revert "iosched: prevent aliased requests from starving other I/O"

This reverts commit d41c5ccd3f2718c5321941c9e63e59a7d2bbcb29.
fix derp
net / netfilter: remove annoying 'comparison will always be true' warning

-adding a new function which avoids this warning
-using the new function in all places where it makes no sense to check

+FIX: fs/sync.c
fs/sync.c:25:1: warning: function declaration isn't a prototype

Conflicts:
	fs/sync.c