[gupnp-av] build: Use -Wno-unused-parameter instead of -Wno-unused-parameters

[Ting-Wei Lan <lantw src gnome org>]

commit c7ee091e303f33e299e94d6d27b94b65ce9779c8
Author: Ting-Wei Lan <lantw src gnome org>
Date:   Wed Jun 17 18:34:01 2015 +0800

    build: Use -Wno-unused-parameter instead of -Wno-unused-parameters
    
    Clang doesn't support -Wno-unused-parameters. We should use the option
    supported by both GCC and Clang.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=751102

 tests/Makefile.am |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 6f81053..148d91e 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -4,7 +4,7 @@ common_cflags = \
        $(LIBGUPNP_CFLAGS) \
        -I$(top_srcdir) \
        $(WARN_CFLAGS) \
-       -Wno-unused-parameters
+       -Wno-unused-parameter
 common_ldadd = \
        $(top_builddir)/libgupnp-av/libgupnp-av-1.0.la \
        $(LIBGUPNP_LIBS)