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/networking/ppp/nix-purity.patch

@@ -0,0 +1,33 @@
+diff --git a/pppd/Makefile.linux b/pppd/Makefile.linux
+index 22837c5..6f6fff5 100644
+--- a/pppd/Makefile.linux
++++ b/pppd/Makefile.linux
+@@ -111,8 +111,8 @@ endif
+ 
+ # EAP SRP-SHA1
+ ifdef USE_SRP
+-CFLAGS	+= -DUSE_SRP -DOPENSSL -I/usr/local/ssl/include
+-LIBS	+= -lsrp -L/usr/local/ssl/lib
++CFLAGS	+= -DUSE_SRP -DOPENSSL -I@openssl_dev@/include/openssl
++LIBS	+= -lsrp -L@openssl_lib@/lib
+ NEEDCRYPTOLIB = y
+ TARGETS	+= srp-entry
+ EXTRAINSTALL = $(INSTALL) -c -m 555 srp-entry $(BINDIR)/srp-entry
+@@ -143,7 +143,7 @@ CFLAGS   += -DHAS_SHADOW
+ #LIBS     += -lshadow $(LIBS)
+ endif
+ 
+-ifeq ($(shell echo '\#include <crypt.h>' | $(CC) -E - >/dev/null 2>&1 && echo yes),yes)
++ifneq ($(wildcard @glibc@/include/crypt.h),)
+ CFLAGS  += -DHAVE_CRYPT_H=1
+ LIBS	+= -lcrypt
+ endif
+@@ -155,7 +155,7 @@ endif
+ 
+ ifdef NEEDDES
+ ifndef USE_CRYPT
+-CFLAGS   += -I$(shell $(CC) --print-sysroot)/usr/include/openssl
++CFLAGS   += -I@openssl_dev@/include/openssl
+ NEEDCRYPTOLIB = y
+ else
+ CFLAGS   += -DUSE_CRYPT=1