libgo patch committed: Avoid error if WIFCONTINUED not defined

[Ian Lance Taylor]

This libgo patch avoids an unused parameter error if WIFCONTINUED is
not defined on the system.  This fixes GCC PR 90614.  Bootstrapped and
ran Go tests on x86_64-pc-linux-gnu.  Committed to trunk and GCC 9
branch.

Ian

Index: gcc/go/gofrontend/MERGE
===================================================================
--- gcc/go/gofrontend/MERGE     (revision 271322)
+++ gcc/go/gofrontend/MERGE     (working copy)
@@ -1,4 +1,4 @@
-54aacecc8167bfba8420cb7b245787ff80bde61b
+578c4fb6132801db8e9d11d741d2394e07c5a398
 
 The first line of this file holds the git revision number of the last
 merge done from the gofrontend repository.
Index: libgo/go/syscall/wait.c
===================================================================
--- libgo/go/syscall/wait.c     (revision 271182)
+++ libgo/go/syscall/wait.c     (working copy)
@@ -51,7 +51,7 @@ extern _Bool Continued (uint32_t *w)
   __asm__ (GOSYM_PREFIX "syscall.WaitStatus.Continued");
 
 _Bool
-Continued (uint32_t *w)
+Continued (uint32_t *w __attribute__ ((unused)))
 {
   return WIFCONTINUED (*w) != 0;
 }