Check $READELF_FOR_TARGET for readelf in configure

Similar to as, ld, nm and objdump, gcc configure should check
$READELF_FOR_TARGET for readelf.

	PR bootstrap/67385
	* configure.ac (gcc_cv_readelf): Check $READELF_FOR_TARGET.
	* configure: Regenerated.

From-SVN: r228567

gcc/ChangeLog

 2015-10-07  H.J. Lu  <hongjiu.lu@intel.com>
 
+	PR bootstrap/67385
+	* configure.ac (gcc_cv_readelf): Check $READELF_FOR_TARGET.
+	* configure: Regenerated.
+
+2015-10-07  H.J. Lu  <hongjiu.lu@intel.com>
+
 	PR target/67850
 	* config/i386/i386.c (ix86_maybe_switch_abi): Merged with ...
 	(ix86_set_current_function): This.

gcc/configure

@@ -22271,9 +22271,11 @@ if test -f $gcc_cv_binutils_srcdir/configure.ac \
 	gcc_cv_readelf=../binutils/readelf$build_exeext
 elif test -x readelf$build_exeext; then
 	gcc_cv_readelf=./readelf$build_exeext
+elif ( set dummy $READELF_FOR_TARGET; test -x $2 ); then
+        gcc_cv_readelf="$READELF_FOR_TARGET"
 else
-        # Extract the first word of "readelf", so it can be a program name with args.
-set dummy readelf; ac_word=$2
+        # Extract the first word of "$READELF_FOR_TARGET", so it can be a program name with args.
+set dummy $READELF_FOR_TARGET; ac_word=$2
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
 $as_echo_n "checking for $ac_word... " >&6; }
 if test "${ac_cv_path_gcc_cv_readelf+set}" = set; then :

gcc/configure.ac

@@ -2403,8 +2403,10 @@ if test -f $gcc_cv_binutils_srcdir/configure.ac \
 	gcc_cv_readelf=../binutils/readelf$build_exeext
 elif test -x readelf$build_exeext; then
 	gcc_cv_readelf=./readelf$build_exeext
+elif ( set dummy $READELF_FOR_TARGET; test -x $[2] ); then
+        gcc_cv_readelf="$READELF_FOR_TARGET"
 else
-        AC_PATH_PROG(gcc_cv_readelf, readelf)
+        AC_PATH_PROG(gcc_cv_readelf, $READELF_FOR_TARGET)
 fi])
 
 AC_MSG_CHECKING(what readelf to use)