common-user: Fix tail calls to safe_syscall_set_errno_tail

For the ABIs in which the syscall return register is not
also the first function argument register, move the errno
value into the correct place.

Fixes: a3310c0397 ("linux-user: Move syscall error detection into safe_syscall_base")
Reported-by: Laurent Vivier <laurent@vivier.eu>
Tested-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220104190454.542225-1-richard.henderson@linaro.org>

common-user/host/i386/safe-syscall.inc.S

@@ -120,6 +120,7 @@ safe_syscall_end:
         pop     %ebp
         .cfi_adjust_cfa_offset -4
         .cfi_restore ebp
+        mov     %eax, (%esp)
         jmp     safe_syscall_set_errno_tail
 
         .cfi_endproc

common-user/host/mips/safe-syscall.inc.S

@@ -141,6 +141,7 @@ safe_syscall_end:
 1:      USE_ALT_CP(t0)
         SETUP_GPX(t1)
         SETUP_GPX64(t0, t1)
+        move    a0, v0
         PTR_LA  t9, safe_syscall_set_errno_tail
         jr      t9
 

common-user/host/x86_64/safe-syscall.inc.S

@@ -99,6 +99,7 @@ safe_syscall_end:
 1:      pop     %rbp
         .cfi_def_cfa_offset 8
         .cfi_restore rbp
+        mov     %eax, %edi
         jmp     safe_syscall_set_errno_tail
         .cfi_endproc