Fix ICE due to subreg:us_truncate.

Fix ICE due to subreg:us_truncate.

Force_operand issues an ICE when input
is (subreg:DI (us_truncate:V8QI)), it's probably because it's an
invalid rtx, So refine backend patterns for that.

gcc/ChangeLog:

	PR target/117318
	* config/i386/sse.md (*avx512vl_<code>v2div2qi2_mask_store_1):
	Rename to ..
	(avx512vl_<code>v2div2qi2_mask_store_1): .. this.
	(avx512vl_<code>v2div2qi2_mask_store_2): Change to
	define_expand.
	(*avx512vl_<code><mode>v4qi2_mask_store_1): Rename to ..
	(avx512vl_<code><mode>v4qi2_mask_store_1): .. this.
	(avx512vl_<code><mode>v4qi2_mask_store_2): Change to
	define_expand.
	(*avx512vl_<code><mode>v8qi2_mask_store_1): Rename to ..
	(avx512vl_<code><mode>v8qi2_mask_store_1): .. this.
	(avx512vl_<code><mode>v8qi2_mask_store_2): Change to
	define_expand.
	(*avx512vl_<code><mode>v4hi2_mask_store_1): Rename to ..
	(avx512vl_<code><mode>v4hi2_mask_store_1): .. this.
	(avx512vl_<code><mode>v4hi2_mask_store_2): Change to
	define_expand.
	(*avx512vl_<code>v2div2hi2_mask_store_1): Rename to ..
	(avx512vl_<code>v2div2hi2_mask_store_1): .. this.
	(avx512vl_<code>v2div2hi2_mask_store_2): Change to
	define_expand.
	(*avx512vl_<code>v2div2si2_mask_store_1): Rename to ..
	(avx512vl_<code>v2div2si2_mask_store_1): .. this.
	(avx512vl_<code>v2div2si2_mask_store_2): Change to
	define_expand.
	(*avx512f_<code>v8div16qi2_mask_store_1): Rename to ..
	(avx512f_<code>v8div16qi2_mask_store_1): .. this.
	(avx512f_<code>v8div16qi2_mask_store_2): Change to
	define_expand.

gcc/testsuite/ChangeLog:

	* gcc.target/i386/pr117318.c: New test.