aarch64: XFAIL some SME tests for BE

aarch64: XFAIL some SME tests for BE

The z0_z23 tests rely on being able to propagate:

  (1) set of double-register z0-z1
  (2) copy of z0 to z28
  (3) use of z28

to a use of z0.  On LE targets it's regcprop that does this.
But regcprop punts on (2) because of:

  https://gcc.gnu.org/pipermail/gcc-patches/2002-July/081990.html

This patch therefore XFAILs the affected tests.

gcc/testsuite/
	* gcc.target/aarch64/sme2/acle-asm/uzp_bf16_x2.c: XFAIL z0_z23 tests
	for big-endian.
	* gcc.target/aarch64/sme2/acle-asm/uzp_f16_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/uzp_f32_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/uzp_f64_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/uzp_s16_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/uzp_s32_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/uzp_s64_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/uzp_s8_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/uzp_u16_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/uzp_u32_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/uzp_u64_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/uzp_u8_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/uzpq_bf16_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/uzpq_f16_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/uzpq_f32_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/uzpq_f64_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/uzpq_s16_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/uzpq_s32_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/uzpq_s64_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/uzpq_s8_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/uzpq_u16_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/uzpq_u32_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/uzpq_u64_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/uzpq_u8_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/zip_bf16_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/zip_f16_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/zip_f32_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/zip_f64_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/zip_s16_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/zip_s32_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/zip_s64_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/zip_s8_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/zip_u16_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/zip_u32_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/zip_u64_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/zip_u8_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/zipq_bf16_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/zipq_f16_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/zipq_f32_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/zipq_f64_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/zipq_s16_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/zipq_s32_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/zipq_s64_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/zipq_s8_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/zipq_u16_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/zipq_u32_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/zipq_u64_x2.c: Likewise.
	* gcc.target/aarch64/sme2/acle-asm/zipq_u8_x2.c: Likewise.