Fix: change XBMC temp folder path to a non-root accessible folder

let XBMC store its temp (and xbmc.log) in XBMC_HOME/.xbmc/temp instead of /data/data/org.xbmc.xbmc/....

When XBMC_TEMP is not defined, https://github.com/xbmc/xbmc/blob/d128d3760cb16bba81bcfaaa0498bc8a58ff115e/xbmc/Application.cpp#L1058 will take care of it and change it to XBMC_HOME