maint: STREQ → streq

Use new Gnulib streq function instead of rolling our own macro.
* bootstrap.conf (gnulib_modules): Add stringeq.
* src/rm.c (main): Don’t assume streq is a macro that expands to (...),
as it is now a function.
* src/system.h:
* tests/df/no-mtab-status.sh, tests/df/skip-duplicates.sh:
(STREQ): Remove.  All uses replaced by streq.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/env.c b/src/env.c
index baa1e1372..e06ca5568 100644
--- a/src/env.c
+++ b/src/env.c
@@ -831,7 +831,7 @@ main (int argc, char **argv)
         }
     }
 
-  if (optind < argc && STREQ (argv[optind], "-"))
+  if (optind < argc && streq (argv[optind], "-"))
     {
       ignore_environment = true;
       ++optind;