LoongArch: extable: Add type and data fields

This is a LoongArch port of commit d6e2cc5647 ("arm64: extable: add
`type` and `data` fields").

Subsequent patches will add specialized handlers for fixups, in addition
to the simple PC fixup we have today. In preparation, this patch adds a
new `type` field to struct exception_table_entry, and uses this to
distinguish the fixup and other cases. A `data` field is also added so
that subsequent patches can associate data specific to each exception
site (e.g. register numbers).

Handlers are named ex_handler_*() for consistency, following the example
of x86. At the same time, get_ex_fixup() is split out into a helper so
that it can be used by other ex_handler_*() functions in the subsequent
patches.

Signed-off-by: Youling Tang <tangyouling@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

scripts/sorttable.c

@@ -304,6 +304,7 @@ static int do_file(char const *const fname, void *addr)
 	switch (r2(&ehdr->e_machine)) {
 	case EM_386:
 	case EM_AARCH64:
+	case EM_LOONGARCH:
 	case EM_RISCV:
 	case EM_S390:
 	case EM_X86_64:
@@ -312,7 +313,6 @@ static int do_file(char const *const fname, void *addr)
 	case EM_PARISC:
 	case EM_PPC:
 	case EM_PPC64:
-	case EM_LOONGARCH:
 		custom_sort = sort_relative_table;
 		break;
 	case EM_ARCOMPACT: