re PR go/78172 (gen-sysinfo.go vs AIX cred.h)

	PR go/78172.
    libgo: avoid confusion in upcase_fields in mksysinfo.sh
    
    The mksysinfo.sh script could get confused when there were multiple
    types starting with the same name.  I believe this is the underlying
    cause of GCC PR 78172.
    
    Also redirect a grep to /dev/null to avoid extraneous messages during
    the build.
    
    Reviewed-on: https://go-review.googlesource.com/32821

From-SVN: r241868

gcc/go/gofrontend/MERGE

-150bca67d8bb4b23009f53ba06e85e306e3960d8
+afe0456d25e3c6c0d91a8fd4c0fdfdbaa35cc251
 
 The first line of this file holds the git revision number of the last
 merge done from the gofrontend repository.

libgo/mksysinfo.sh

@@ -188,7 +188,7 @@ grep '^const _EPOLL' gen-sysinfo.go |
   grep -v EPOLLET |
   sed -e 's/^\(const \)_\(EPOLL[^= ]*\)\(.*\)$/\1\2 = _\2/' >> ${OUT}
 # Make sure EPOLLET is positive.
-if grep '^const _EPOLLET = [0-9]' gen-sysinfo.go; then
+if grep '^const _EPOLLET = [0-9]' gen-sysinfo.go >/dev/null 2>&1; then
   grep '^const _EPOLLET ' gen-sysinfo.go |
     sed -e 's/^\(const \)_\(EPOLL[^= ]*\)\(.*\)$/\1\2 = _\2/' >> ${OUT}
 else
@@ -268,7 +268,7 @@ fi
 # is not empty, the structure or type is renamed to $2.
 upcase_fields () {
   name="$1"
-  def=`grep "^type $name" gen-sysinfo.go`
+  def=`grep "^type $name " gen-sysinfo.go`
   fields=`echo $def | sed -e 's/^[^{]*{\(.*\)}$/\1/'`
   prefix=`echo $def | sed -e 's/{.*//'`
   if test "$2" != ""; then