Bug#725703: Should be safe to enable

[Martin Perazzo <martin.perazzo@gmail.com>]

ZSWAP requires to compile the kernel with CONFIG_ZSWAP=y in config
Being a new feature, its disabled by default. Requires boot time option 
zswap.enabled=1 to be passed into the kernel to be enabled.
Compile it in shouldn't cause any ill effects.

https://www.kernel.org/doc/Documentation/vm/zswap.txt