Add option to nm to change the characters displayed for ifunc symbols. Add a configure time option to change the default characters.

PR 22967
	* nm.c (ifunc_type_chars): New variable.
	(long_options): Add --ifunc-chars.
	(print_symbol): Use ifunc_type_chars for ifunc symbols.
	(main): Handle the new option.
	* doc/binutils.texi: Document the new option.
	* configure.ac: Add --enable-f-for-ifunc-symbols option which
	changes the default symbol displayed by nm.
	* NEWS: Mention the new feature.
	* testsuite/binutils-all/nm.exp: Test the new feature.
	* config.in: Regenerate.
	* configure: Regenerate.

binutils/testsuite/binutils-all/nm.exp

@@ -298,6 +298,49 @@ if [is_elf_format] {
 	    remote_file host delete $tmpfile
 	}
     }
+
+    # PR 22967
+    # Test nm --ifunc-chars on a indirect symbols.
+    
+    # The following targets are known to not support ifuncs.
+    setup_xfail "alpha*-*-*"
+    setup_xfail "arm*-*-nto*"
+    setup_xfail "arm*-*-netbsdelf*"
+    setup_xfail "mips*-*-*"
+    setup_xfail "msp430*-*-*"
+    setup_xfail "tx39*-*-*"
+    setup_xfail "visium*-*-*"
+
+    set testname "nm --ifunc-chars"
+    if {![binutils_assemble $srcdir/$subdir/ifunc.s tmpdir/ifunc.o]} then {
+	fail "$testname (assembly)"
+    } else {
+	if [is_remote host] {
+	    set tmpfile [remote_download host tmpdir/ifunc.o]
+	} else {
+	    set tmpfile tmpdir/ifunc.o
+	}
+
+	set got [binutils_run $NM "$NMFLAGS --ifunc-chars=Ff $tmpfile"]
+
+	if [regexp "F global_foo" $got] then {
+	    pass "$testname (global ifunc)"
+	} else {
+	    fail "$testname (global ifunc)"
+	}
+
+	if [regexp "f local_foo" $got] then {
+	    pass "$testname (local ifunc)"
+	} else {
+	    fail "$testname (local ifunc)"
+	}
+
+	if { $verbose < 1 } {
+	    remote_file host delete "tmpdir/ifunc.o"
+	}
+    }
+
+    
 }
 
 # There are certainly other tests that could be run.