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/applications/misc/xmrig/donate-level.patch

@@ -0,0 +1,12 @@
+diff --git a/src/donate.h b/src/donate.h
+--- a/src/donate.h
++++ b/src/donate.h
+@@ -46,6 +46,6 @@
+  */
+-constexpr const int kDefaultDonateLevel = 1;
+-constexpr const int kMinimumDonateLevel = 1;
++constexpr const int kDefaultDonateLevel = @donateLevel@;
++constexpr const int kMinimumDonateLevel = @donateLevel@;
+ 
+ 
+ #endif /* XMRIG_DONATE_H */