linux-user: elfload: Add more initial s390x PSW bits

Make the PSW look more similar to the real s390x userspace PSW.
Except for being there, the newly added bits should not affect the
userspace code execution.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Message-Id: <20230704081506.276055-2-iii@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>

linux-user/elfload.c

@@ -1635,7 +1635,9 @@ const char *elf_hwcap_str(uint32_t bit)
 static inline void init_thread(struct target_pt_regs *regs, struct image_info *infop)
 {
     regs->psw.addr = infop->entry;
-    regs->psw.mask = PSW_MASK_64 | PSW_MASK_32;
+    regs->psw.mask = PSW_MASK_DAT | PSW_MASK_IO | PSW_MASK_EXT | \
+                     PSW_MASK_MCHECK | PSW_MASK_PSTATE | PSW_MASK_64 | \
+                     PSW_MASK_32;
     regs->gprs[15] = infop->start_stack;
 }