[POWERPC] Fix compiler warning message on get_property call

This fixes the warning message from the return value of function
get_property(), by making sure that the variable that receives the
value is marked as const.

Signed-off-by: Roy Zang	<tie-fei.zang@freescale.com>

--
Signed-off-by: Paul Mackerras <paulus@samba.org>
1 file changed