Make libav conflict with ffmpeg

packages/libav/build.sh

@@ -1,10 +1,11 @@
 TERMUX_PKG_HOMEPAGE=http://libav.org/
 TERMUX_PKG_DESCRIPTION="Tools and libraries to manipulate a wide range of multimedia formats and protocols"
 TERMUX_PKG_VERSION=11.4
-TERMUX_PKG_BUILD_REVISION=1
+TERMUX_PKG_BUILD_REVISION=2
 TERMUX_PKG_SRCURL=http://libav.org/releases/libav-${TERMUX_PKG_VERSION}.tar.xz
 # libbz2 is used by matroska decoder:
 TERMUX_PKG_DEPENDS="openssl, libbz2, libx264, xvidcore, libvorbis, libfaac"
+TERMUX_PKG_CONFLICTS="ffmpeg"
 
 termux_step_configure () {
 	cd $TERMUX_PKG_BUILDDIR
@@ -13,8 +14,7 @@ termux_step_configure () {
 	elif [ $TERMUX_ARCH = "i686" ]; then
 		_ARCH="x86"
 	else
-		echo "Unsupported arch: $TERMUX_ARCH"
-		exit 1
+		_ARCH=$TERMUX_ARCH
 	fi
         # --disable-asm to prevent text relocations
 	$TERMUX_PKG_SRCDIR/configure \