uboot: (firmwareOdroidC2/C4) don't invoke patch tool, use patches = [] instead

https://github.com/NixOS/nixpkgs/blob/master/pkgs/stdenv/generic/setup.sh#L948
this can do it nicely.

Signed-off-by: Anton Arapov <anton@deadbeef.mx>

pkgs/build-support/setup-hooks/find-xml-catalogs.sh

@@ -0,0 +1,22 @@
+addXMLCatalogs () {
+    local d i
+    # ‘xml/dtd’ and ‘xml/xsl’ are deprecated. Catalogs should be
+    # installed underneath ‘share/xml’.
+    for d in $1/share/xml $1/xml/dtd $1/xml/xsl; do
+        if [ -d $d ]; then
+            for i in $(find $d -name catalog.xml); do
+                XML_CATALOG_FILES+=" $i"
+            done
+        fi
+    done
+}
+
+if [ -z "${libxmlHookDone-}" ]; then
+    libxmlHookDone=1
+
+    # Set up XML_CATALOG_FILES.  An empty initial value prevents
+    # xmllint and xsltproc from looking in /etc/xml/catalog.
+    export XML_CATALOG_FILES=''
+    if [ -z "$XML_CATALOG_FILES" ]; then XML_CATALOG_FILES=" "; fi
+    addEnvHooks "$hostOffset" addXMLCatalogs
+fi