Switch from using 'nacl_main' to 'main' entry point

ports/perl/build.sh

 # Copyright (c) 2015 The Native Client Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # falling back to cc for generating build time artifacts
 export BUILD_CC=cc
 export BUILD_LD=cc
 # use -Wno-return-type to suppress return-type errors encountered
 # with pnacl, arm's clang-newlib (microperl)
 NACLPORTS_CFLAGS_MICRO=$NACLPORTS_CFLAGS
-NACLPORTS_CFLAGS_MICRO+=" -Dmain=nacl_main -Wno-return-type "
+NACLPORTS_CFLAGS_MICRO+=" -Wno-return-type "
 NACLPORTS_CFLAGS+=" -I${NACL_SDK_ROOT}/include -I${NACLPORTS_INCLUDE} \
   -Wno-return-type"
 BUILD_DIR=${SRC_DIR}
 # keeping microperl for now
 EXECUTABLES="perl microperl"
-NACLPORTS_LDFLAGS+=" ${NACL_CLI_MAIN_LIB}"
+NACLPORTS_LDFLAGS+=" ${NACL_CLI_MAIN_LDFLAGS}"
 # we need a working perl on host to build things for target
 HOST_BUILD=${WORK_DIR}/build_host
 ARCH_DIR=${PUBLISH_DIR}/${NACL_ARCH}
 NACLPORTS_LIBS=" ${NACL_CLI_MAIN_LIB}"
 # PNaCl and newlib dont have dynamic loading, so
 # using Perl's internal stub file dl_none.xs
 # specifically for systems which do not support it
 # Also, FILE pointer is structured a bit differently
 # Relevant stdio parameters found via sel_ldr on Linux
 if [ "${NACL_LIBC}" = "newlib" -o "${NACL_ARCH}" = "pnacl" ] ; then
@@ skipping 148 matching lines @@
   EXPECTED=${START_DIR}/expected_${TOOLCHAIN}.txt
   if ! cmp tests_out.txt ${EXPECTED}; then
     echo "Test output did not match expected output"
     echo "See ${PWD}/tests_err.txt"
     diff -u tests_out.txt ${EXPECTED}
     exit 1
   fi
 
   echo "PASSED"
 }