Remove track points with 0 coordinates from a GPX file

null_island.xslt

<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:m="http://www.topografix.com/GPX/1/1">
    <xsl:template match="m:trkpt[@lon='0'][@lat='0']" />
    <xsl:template match="@*|node()">
        <xsl:copy>
            <xsl:apply-templates select="@*|node()" />
        </xsl:copy>
    </xsl:template>
</xsl:stylesheet>