kalua: init: zram: harmonize with openwrt-version (set to startup at position 15): https://dev.openwrt.org/changeset/35028/trunk
(cherry picked from commit 0b2eab06559e766081cdf39d3fd364df2405fb35)

Signed-off-by: Andi Bräu <ab@andi95.de>
kalua: init: zram: comment in sourcecode
(cherry picked from commit 048036e121d8c2433760430328eb23662ee02188)

Signed-off-by: Andi Bräu <ab@andi95.de>
kalua: init: zram: always reset zramdev, before activating - have seen situations, where writing disksize fails, e.g. zram stop; wc -c /dev/zram0; zram start
(cherry picked from commit cf6ab2b9d3aab533e83a98339692785306f1ec55)

Signed-off-by: Andi Bräu <ab@andi95.de>
kalua: init: zram: only reset device, if loaded - so a double stop() does not throw errors
(cherry picked from commit fa0fd7b017e56962894b93afb6ef49d88523a612)

Signed-off-by: Andi Bräu <ab@andi95.de>
kalua: init: zram: support for loading/unloading zram-related kernel-modules, especially for stop()
(cherry picked from commit b9aa96548680f2c333ceeebf491c864f9a9dac68)

Signed-off-by: Andi Bräu <ab@andi95.de>
kalua: init: zram: support for multiple cpu-cores
(cherry picked from commit f731b711440eab64f64781007c3ef5663aa5fece)

Signed-off-by: Andi Bräu <ab@andi95.de>