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/os-specific/linux/bridge-utils/autoconf-ar.patch

@@ -0,0 +1,21 @@
+--- a/configure.ac
++++ b/configure.ac
+@@ -9,6 +9,7 @@ dnl Checks for programs.
+ AC_PROG_CC
+ AC_PROG_INSTALL
+ AC_PROG_RANLIB
++AC_CHECK_TOOL([AR], [ar])
+ 
+ dnl Checks for header files.
+ AC_HEADER_STDC
+--- a/libbridge/Makefile.in
++++ b/libbridge/Makefile.in
+@@ -1,7 +1,7 @@
+ 
+ KERNEL_HEADERS=-I@KERNEL_HEADERS@
+ 
+-AR=ar
++AR=@AR@
+ RANLIB=@RANLIB@
+ 
+ CC=@CC@