bfq-iosched: Tuning for SSD
bfq-iosched: Set bfq_back_penalty = 1
drivers: mmc: disable CRC.

Signed-off-by: Francisco Franco <franciscofranco.1990@gmail.com>
Signed-off-by: Seongmin Park <r_data@naver.com>
cfq-iosched: update tunables with mainline
sched/debug: disable sched debug sysrq by default - increase performance
int_sqrt: Correction square root algo with naming
int_sqrt: Improve 3x faster integer sqrt.

Result on 10,000,000 call.
Old:
sqrt(12345689) = 3513
real	0m0.768s
user	0m0.760s
sys	0m0.004s

New:
sqrt(12345689) = 3513
real	0m0.222s
user	0m0.224s
sys	0m0.000s
readahead: optimize divide/multiply by power of 2 using L/R shift

Conflicts:
	mm/readahead.c
readahead: optimize divide/multiply by power of 2 using L/R shift - Fix
slub.c: Remove PAGE_ALLOC_COSTLY_ORDER - +3% boost