Remove unwanted metadata from SVG files. (Closes: #956102)

softwaves-theme/wallpaper/contents/images/1280x720.svg

@@ -20,7 +20,6 @@
    xml:space="preserve"
    inkscape:version="0.91 r13725"
    sodipodi:docname="1280x720.svg"
-   inkscape:export-filename=""
    inkscape:export-xdpi="120"
    inkscape:export-ydpi="120"><metadata
      id="metadata4579"><rdf:RDF><cc:Work

softwaves-theme/wallpaper/contents/images/1920x1080.svg

@@ -20,7 +20,6 @@
    xml:space="preserve"
    inkscape:version="0.92.0 r15299"
    sodipodi:docname="1920x1080.svg"
-   inkscape:export-filename=""
    inkscape:export-xdpi="120"
    inkscape:export-ydpi="120"><metadata
      id="metadata4579"><rdf:RDF><cc:Work

softwaves-theme/wallpaper/contents/images/2560x1440.svg

@@ -20,7 +20,6 @@
    xml:space="preserve"
    inkscape:version="0.91 r13725"
    sodipodi:docname="2560x1440.svg"
-   inkscape:export-filename=""
    inkscape:export-xdpi="120"
    inkscape:export-ydpi="120"><metadata
      id="metadata4579"><rdf:RDF><cc:Work

softwaves-theme/wallpaper/contents/images/3840x2160.svg

@@ -20,7 +20,6 @@
    xml:space="preserve"
    inkscape:version="0.92.0 r15299"
    sodipodi:docname="3840x2160.svg"
-   inkscape:export-filename=""
    inkscape:export-xdpi="120"
    inkscape:export-ydpi="120"><metadata
      id="metadata4579"><rdf:RDF><cc:Work