objtool: Reorganize cmdline options

Split the existing options into two groups: actions, which actually do
something; and options, which modify the actions in some way.

Also there's no need to have short flags for all the non-action options.
Reserve short flags for the more important actions.

While at it:

- change a few of the short flags to be more intuitive

- make option descriptions more consistently descriptive

- sort options in the source like they are when printed

- move options to a global struct

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Link: https://lkml.kernel.org/r/9dcaa752f83aca24b1b21f0b0eeb28a0c181c0b0.1650300597.git.jpoimboe@redhat.com

tools/objtool/arch/x86/decode.c

@@ -581,7 +581,7 @@ int arch_decode_instruction(struct objtool_file *file, const struct section *sec
 		break;
 
 	case 0xc7: /* mov imm, r/m */
-		if (!noinstr)
+		if (!opts.noinstr)
 			break;
 
 		if (insn.length == 3+4+4 && !strncmp(sec->name, ".init.text", 10)) {

tools/objtool/arch/x86/special.c

@@ -20,7 +20,7 @@ void arch_handle_alternative(unsigned short feature, struct special_alt *alt)
 		 * find paths that see the STAC but take the NOP instead of
 		 * CLAC and the other way around.
 		 */
-		if (uaccess)
+		if (opts.uaccess)
 			alt->skip_orig = true;
 		else
 			alt->skip_alt = true;