Don't push LDFLAGS/CFLAGS for iconv.
Just assume they're covered somewhere else.
Otherwise we get -L/usr/lib and -I/usr/include search paths with uClibc
internal iconv support, which breaks things.

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>

diff -Nura php-5.3.13/configure php-5.3.13-iconv/configure
--- php-5.3.13/configure	2012-05-08 06:41:23.000000000 -0300
+++ php-5.3.13-iconv/configure	2012-05-18 22:18:21.313975849 -0300
@@ -47885,8 +47885,8 @@
       PHP_ICONV_PREFIX="$ICONV_DIR"
     fi
 
-    CFLAGS="-I$PHP_ICONV_PREFIX/include $CFLAGS"
-    LDFLAGS="-L$PHP_ICONV_PREFIX/$PHP_LIBDIR $LDFLAGS"
+    #CFLAGS="-I$PHP_ICONV_PREFIX/include $CFLAGS"
+    #LDFLAGS="-L$PHP_ICONV_PREFIX/$PHP_LIBDIR $LDFLAGS"
 
     if test -r "$PHP_ICONV_PREFIX/include/giconv.h"; then
       PHP_ICONV_H_PATH="$PHP_ICONV_PREFIX/include/giconv.h"