configure.ac: Just look for png, not png12
diff --git a/configure.ac b/configure.ac
index 81f90b6..a75039c 100644
--- a/configure.ac
+++ b/configure.ac
@@ -35,7 +35,7 @@
 AC_SUBST(DLOPEN_LIBS)
 
 PKG_CHECK_MODULES(COMPOSITOR,
-		  [wayland-server egl >= 7.10 glesv2 pixman-1 libpng12])
+		  [wayland-server egl >= 7.10 glesv2 pixman-1 libpng])
 
 AC_CHECK_PROG(RSVG_CONVERT, rsvg-convert, rsvg-convert)
 AM_CONDITIONAL(HAVE_RSVG_CONVERT, test -n "$RSVG_CONVERT")