[gcc r12-7314] runtime/internal/syscall: build dummy package if not Linux

[Ian Lance Taylor]

https://gcc.gnu.org/g:a7eeaa48986f37badb78717e3c138a8d02bb01a6

commit r12-7314-ga7eeaa48986f37badb78717e3c138a8d02bb01a6
Author: Ian Lance Taylor <iant@golang.org>
Date:   Mon Feb 21 09:50:28 2022 -0800

    runtime/internal/syscall: build dummy package if not Linux
    
    Fixes libgo build on non-Linux systems.
    
    Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/387134

Diff:
---
 gcc/go/gofrontend/MERGE                            | 2 +-
 libgo/go/runtime/internal/syscall/syscall_other.go | 7 +++++++
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/gcc/go/gofrontend/MERGE b/gcc/go/gofrontend/MERGE
index 3c0380e8285..7455d01c179 100644
--- a/gcc/go/gofrontend/MERGE
+++ b/gcc/go/gofrontend/MERGE
@@ -1,4 +1,4 @@
-20e74f9ef8206fb02fd28ce3d6e0f01f6fb95dc9
+aee8eddbfc3ef1b03353a060e79e7d668fb229e2
 
 The first line of this file holds the git revision number of the last
 merge done from the gofrontend repository.
diff --git a/libgo/go/runtime/internal/syscall/syscall_other.go b/libgo/go/runtime/internal/syscall/syscall_other.go
new file mode 100644
index 00000000000..c0945ceec09
--- /dev/null
+++ b/libgo/go/runtime/internal/syscall/syscall_other.go
@@ -0,0 +1,7 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !linux
+
+package syscall