objtool: Fix standalone --hacks=jump_label

The objtool command line 'objtool --hacks=jump_label foo.o' on its own
should be expected to rewrite jump labels to NOPs. This means the
add_special_section_alts() code path needs to run when only this option
is provided.

This is mainly relevant in certain debugging situations, but could
potentially also fix kernel builds in which objtool is run with
--hacks=jump_label but without --orc, --stackval, --uaccess, or
--hacks=noinstr.

Fixes: de6fbce ("objtool: Read special sections with alts only when specific options are selected")
Signed-off-by: Dylan Hatch <dylanbhatch@google.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>

Author: dylanbhatch

tools/objtool/check.c

@@ -2563,7 +2563,8 @@ static int decode_sections(struct objtool_file *file)
 	 * Must be before add_jump_destinations(), which depends on 'func'
 	 * being set for alternatives, to enable proper sibling call detection.
 	 */
-	if (opts.stackval || opts.orc || opts.uaccess || opts.noinstr) {
+	if (opts.stackval || opts.orc || opts.uaccess || opts.noinstr ||
+	    opts.hack_jump_label) {
 		ret = add_special_section_alts(file);
 		if (ret)
 			return ret;