[packages/firefox] bump required libpng version

[atler]

commit 2128fb76cf5b0cd2bb70ede5df2a0005e9608d40
Author: Jan Palus <atler at pld-linux.org>
Date:   Thu Oct 12 00:21:25 2017 +0200

    bump required libpng version

 firefox.spec | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/firefox.spec b/firefox.spec
index 14bb26e..ed95bb4 100644
--- a/firefox.spec
+++ b/firefox.spec
@@ -277,7 +277,7 @@ BuildRequires:	libffi-devel >= 6:3.0.9
 BuildRequires:	libjpeg-devel >= 6b
 BuildRequires:	libjpeg-turbo-devel
 BuildRequires:	libpng(APNG)-devel >= 0.10
-BuildRequires:	libpng-devel >= 2:1.6.28
+BuildRequires:	libpng-devel >= 2:1.6.31
 BuildRequires:	libstdc++-devel >= 6:4.4
 BuildRequires:	libvpx-devel >= 1.5.0
 BuildRequires:	nspr-devel >= 1:%{nspr_ver}
@@ -326,7 +326,7 @@ Requires:	glib2 >= 1:2.22
 %{?with_gtk3:Requires:	gtk+3 >= 3.4.0}
 Requires:	hicolor-icon-theme
 Requires:	libjpeg-turbo
-Requires:	libpng >= 2:1.6.28
+Requires:	libpng >= 2:1.6.31
 Requires:	libpng(APNG) >= 0.10
 Requires:	libvpx >= 1.5.0
 Requires:	myspell-common
================================================================

---- gitweb:

http://git.pld-linux.org/gitweb.cgi/packages/firefox.git/commitdiff/2128fb76cf5b0cd2bb70ede5df2a0005e9608d40