ld: Improve --fatal-warnings for unknown command-line options

There are 2 problems with --fatal-warnings for unknown command-line
options:

1. --fatal-warnings doesn't trigger an error for an unknown command-line
option when --fatal-warnings is the last command-line option.
2. When --fatal-warnings triggers an error for an unknown command-line
option, the message says that the unknown command-line option is ignored.

This patch queues unknown command-line option warnings and outputs queued
command-line option warnings after all command-line options have been
processed so that --fatal-warnings can work for unknown command-line
options regardless of the order of --fatal-warnings.

When --fatal-warnings is used, the linker message is changed from

ld: warning: -z bad-option ignored

to

ld: error: unsupported option: -z bad-option

The above also applies to "-z dynamic-undefined-weak" when the known
"-z dynamic-undefined-weak" option is ignored.

	PR ld/31289
	* ldelf.c (ldelf_after_parse): Use queue_unknown_cmdline_warning
	to warn the ignored -z dynamic-undefined-weak option.
	* ldmain.c (main): Call output_unknown_cmdline_warnings after
	calling ldemul_after_parse.
	* ldmisc.c (CMDLINE_WARNING_SIZE): New.
	(cmdline_warning_list): Likewise.
	(cmdline_warning_head): Likewise.
	(cmdline_warning_tail): Likewise.
	(queue_unknown_cmdline_warning): Likewise.
	(output_unknown_cmdline_warnings): Likewise.
	* ldmisc.h (queue_unknown_cmdline_warning): Likewise.
	(output_unknown_cmdline_warnings): Likewise.
	* emultempl/elf.em (gld${EMULATION_NAME}_handle_option): Use
	queue_unknown_cmdline_warning to warn unknown -z option.
	* testsuite/ld-elf/fatal-warnings-1a.d: New file.
	* testsuite/ld-elf/fatal-warnings-1b.d: Likewise.
	* testsuite/ld-elf/fatal-warnings-2a.d: Likewise.
	* testsuite/ld-elf/fatal-warnings-2b.d: Likewise.
	* testsuite/ld-elf/fatal-warnings-3a.d: Likewise.
	* testsuite/ld-elf/fatal-warnings-3b.d: Likewise.
	* testsuite/ld-elf/fatal-warnings-4a.d: Likewise.
	* testsuite/ld-elf/fatal-warnings-4b.d: Likewise.

ld/ldmisc.h

@@ -27,6 +27,8 @@ extern void minfo (const char *, ...);
 extern void info_msg (const char *, ...);
 extern void lfinfo (FILE *, const char *, ...);
 extern void info_assert (const char *, unsigned int);
+extern void queue_unknown_cmdline_warning (const char *, ...);
+extern void output_unknown_cmdline_warnings (void);
 
 #define ASSERT(x) \
 do { if (!(x)) info_assert(__FILE__,__LINE__); } while (0)