avoid some compiler warnings
avoid some compiler warnings

Patch seen here:
http://lists.uclibc.org/pipermail/uclibc/2015-April/048892.html

kraj/uclibc-ng,wbx-github/uclibc-ng,foss-for-synopsys-dwc-arc-processors/uClibc,brgl/uclibc-ng,brgl/uclibc-ng,foss-for-synopsys-dwc-arc-processors/uClibc,foss-for-synopsys-dwc-arc-processors/uClibc,foss-for-synopsys-dwc-arc-processors/uClibc,wbx-github/uclibc-ng,wbx-github/uclibc-ng,brgl/uclibc-ng,kraj/uclibc-ng,kraj/uclibc-ng,kraj/uclibc-ng,wbx-github/uclibc-ng,brgl/uclibc-ng