Php5's configure script seems to be a little bit buggy as
it disables dynamic library support during cross-compiling.
See also http://www.apachefriends.org/f/viewtopic.php?f=6&t=32367
For now, fix this by preventing the configure script overriding
the previously detected value.
git-svn-id: svn://svn.openwrt.org/openwrt/packages@27763 3c298f89-4303-0410-b956-a3cf2f4a3e73