mktemp: raise the priority to avoid conflicting with coreutils

mktemp: raise the priority to avoid conflicting with coreutils

If mktemp and coreutils have the same priority for the 'mktemp' command,
/bin/mktemp might point to different destinations depending on which package
is installed first.

Raise the priority to 200 in mktemp recipe to avoid such problem.

Signed-off-by: Chen Qi <Qi.Chen@windriver.com>