objtool: Make struct entries[] static and const

This data is not modified and not used outside of special.c.

Also adapt its users to the constness.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/r/20221216-objtool-memory-v2-1-17968f85a464@weissschuh.netSigned-off-by: Josh Poimboeuf <jpoimboe@kernel.org>

tools/objtool/special.c

@@ -26,7 +26,7 @@ struct special_entry {
 	unsigned char key; /* jump_label key */
 };
 
-struct special_entry entries[] = {
+static const struct special_entry entries[] = {
 	{
 		.sec = ".altinstructions",
 		.group = true,
@@ -65,7 +65,7 @@ static void reloc_to_sec_off(struct reloc *reloc, struct section **sec,
 	*off = reloc->sym->offset + reloc->addend;
 }
 
-static int get_alt_entry(struct elf *elf, struct special_entry *entry,
+static int get_alt_entry(struct elf *elf, const struct special_entry *entry,
 			 struct section *sec, int idx,
 			 struct special_alt *alt)
 {
@@ -139,7 +139,7 @@ static int get_alt_entry(struct elf *elf, struct special_entry *entry,
  */
 int special_get_alts(struct elf *elf, struct list_head *alts)
 {
-	struct special_entry *entry;
+	const struct special_entry *entry;
 	struct section *sec;
 	unsigned int nr_entries;
 	struct special_alt *alt;