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/tools/backup/zbackup/protobuf-api-change.patch

@@ -0,0 +1,11 @@
+--- a/backup_restorer.cc
++++ b/backup_restorer.cc
+@@ -48,7 +48,7 @@
+   // TODO: this disables size checks for each separate message. Figure a better
+   // way to do this while keeping them enabled. It seems we need to create an
+   // instance of CodedInputStream for each message, but it might be expensive
+-  cis.SetTotalBytesLimit( backupData.size(), -1 );
++  cis.SetTotalBytesLimit( backupData.size() );
+ 
+   // Used when emitting chunks
+   string chunk;