update kernel-features.h with futex features
update kernel-features.h with futex features

Signed-off-by: Austin Foxley <65462a1d10372f5df6b6641242ca623823c369f3@cetoncorp.com>

hjl-tools/uClibc,kraj/uclibc-ng,kraj/uclibc-ng,mephi42/uClibc,skristiansson/uClibc-or1k,wbx-github/uclibc-ng,waweber/uclibc-clang,hjl-tools/uClibc,kraj/uclibc-ng,foss-for-synopsys-dwc-arc-processors/uClibc,hwoarang/uClibc,mephi42/uClibc,mephi42/uClibc,m-labs/uclibc-lm32,majek/uclibc-vx32,hjl-tools/uClibc,foss-for-synopsys-dwc-arc-processors/uClibc,hjl-tools/uClibc,kraj/uClibc,czankel/xtensa-uclibc,m-labs/uclibc-lm32,wbx-github/uclibc-ng,brgl/uclibc-ng,ddcc/klee-uclibc-0.9.33.2,kraj/uclibc-ng,kraj/uClibc,czankel/xtensa-uclibc,foss-xtensa/uClibc,hwoarang/uClibc,groundwater/uClibc,ndmsystems/uClibc,m-labs/uclibc-lm32,atgreen/uClibc-moxie,skristiansson/uClibc-or1k,foss-xtensa/uClibc,foss-for-synopsys-dwc-arc-processors/uClibc,majek/uclibc-vx32,wbx-github/uclibc-ng,hwoarang/uClibc,ndmsystems/uClibc,waweber/uclibc-clang,czankel/xtensa-uclibc,ffainelli/uClibc,ffainelli/uClibc,atgreen/uClibc-moxie,waweber/uclibc-clang,mephi42/uClibc,ysat0/uClibc,waweber/uclibc-clang,ddcc/klee-uclibc-0.9.33.2,groundwater/uClibc,foss-for-synopsys-dwc-arc-processors/uClibc,ddcc/klee-uclibc-0.9.33.2,czankel/xtensa-uclibc,kraj/uClibc,atgreen/uClibc-moxie,majek/uclibc-vx32,hjl-tools/uClibc,groundwater/uClibc,ndmsystems/uClibc,ffainelli/uClibc,ysat0/uClibc,majek/uclibc-vx32,m-labs/uclibc-lm32,atgreen/uClibc-moxie,ndmsystems/uClibc,brgl/uclibc-ng,skristiansson/uClibc-or1k,ysat0/uClibc,ffainelli/uClibc,brgl/uclibc-ng,skristiansson/uClibc-or1k,hwoarang/uClibc,foss-xtensa/uClibc,foss-xtensa/uClibc,ffainelli/uClibc,groundwater/uClibc,wbx-github/uclibc-ng,kraj/uClibc,ddcc/klee-uclibc-0.9.33.2,ysat0/uClibc,brgl/uclibc-ng,groundwater/uClibc