linux-user/elfload: Enable vxe2 on s390x

The vxe2 hwcap is not set for programs running in linux-user, but is
set by a Linux kernel running in softmmu. Add it to the former.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-Id: <20230804233748.218935-2-iii@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Claudio Fontana <cfontana@suse.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>

linux-user/elfload.c

@@ -1614,6 +1614,7 @@ uint32_t get_elf_hwcap(void)
     }
     GET_FEATURE(S390_FEAT_VECTOR, HWCAP_S390_VXRS);
     GET_FEATURE(S390_FEAT_VECTOR_ENH, HWCAP_S390_VXRS_EXT);
+    GET_FEATURE(S390_FEAT_VECTOR_ENH2, HWCAP_S390_VXRS_EXT2);
 
     return hwcap;
 }