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/development/libraries/mediastreamer/plugins_dir.patch

@@ -0,0 +1,18 @@
+diff --git a/src/base/msfactory.c b/src/base/msfactory.c
+index 14f868e3..2e3445a1 100644
+--- a/src/base/msfactory.c
++++ b/src/base/msfactory.c
+@@ -770,7 +770,12 @@ void ms_factory_uninit_plugins(MSFactory *factory){
+ }
+ 
+ void ms_factory_init_plugins(MSFactory *obj) {
+-	if (obj->plugins_dir == NULL) {
++	char *package_plugins_dir;
++	// Force plugin dir from environment variable if set
++	package_plugins_dir = getenv("MEDIASTREAMER_PLUGINS_DIR");
++	if (package_plugins_dir != NULL) {
++		ms_factory_set_plugins_dir(obj, package_plugins_dir);
++	} else if (obj->plugins_dir == NULL) {
+ #ifdef __APPLE__
+ 	char *dir = getPluginsDir();
+ 	if (dir != NULL) {