utils: fix install prefix for getconf
utils: fix install prefix for getconf

So we don't get /usr/usr/bin/getconf when DEVEL_PREFIX="/usr"

Signed-off-by: Natanael Copa <e73df79305d2c30c2a35966f4bca3b7b6f223156@gmail.com>
Signed-off-by: Bernhard Reutner-Fischer <ce1ac9e9ad16abccd7821f371ad381197b4768ac@gmail.com>

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