Revert "DRIVERS: RANDOM: update"

This reverts commit 085651b22db8e5cdbf4bcfc10e1641017cc87fcd.
Revert "random: remove warning"

This reverts commit 939badafd8afc8beb4c57a78429562525c828bb7.
Revert "random: entropy tweaks are all the rage nowadays"

This reverts commit 83f7ef9334e9092583c3affdacc6b4bd65383015.
Revert "random: prevent add_input from doing anything"

This reverts commit 5712a5f410f162835d87b29bae594bead2abe618.
Revert "random: Statically compute poolbitshift, poolbytes, poolbits"

This reverts commit 0d8a9e77f16c3413fe8b85dad4d3c7221bd82dbd.
Revert "random: Account for entropy loss due to overwrites"

This reverts commit 511a29e94b77ff9bb36029ee264d80b969854775.
Revert "sched: add wait_for_completion_io[_timeout]"

This reverts commit 7e157bdae2aa1b199730c1ed8bf5f0d04737b8db.
Revert "block: add REQ_URGENT to request flags"

This reverts commit 3759bee1e119959a1b34e87a62864fae8dc6f4f2.
Revert "lemur_defconfig: enable KUSER_HELPERS"

This reverts commit efcfb486ec41a1e698160b70c3c01c48c87c7afa.
Revert "sched: set sched_mc_power_savings to 2, which is the highest power saving possible value for this tunable. Basically according to http://elinux.org/images/1/1d/Comparing_Power_Saving_Techniques_For_Multicore_ARM_Platforms.pdf this tunable provides serious power saving improvements close to the power savings of hotpluging cores. Since in this Kernel we're using always a minimum of 2 cpus online at any time during screen off we might actually benefit from this because this feature packs tasks together and try to bind them to cpu0, which in theory will let cpu1 idle longer, thus improving battery life."

This reverts commit 2e745e37f714c95b95b4834fb154c3c5219d28d5.