kernel: reduce spurious rebuilds of simple kmod-* packages

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@37403 3c298f89-4303-0410-b956-a3cf2f4a3e73
kernel: make kmod-sched depend on kmod-ipt-core

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@37404 3c298f89-4303-0410-b956-a3cf2f4a3e73
build: fix IGNORE_ERRORS for sources packages that match both 'y' and 'm'

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@37405 3c298f89-4303-0410-b956-a3cf2f4a3e73
kernel: sctp depends on ipv6 if ipv6 is enabled

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@37406 3c298f89-4303-0410-b956-a3cf2f4a3e73
kernel: fix accidental depends line duplication

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@37407 3c298f89-4303-0410-b956-a3cf2f4a3e73