downloadfiles: add variant to change uEnv.txt

should be one of
- bpi-r3-mini
- bpi-r4-2g5
- bpi-r4-pro
- bpi-r4-lite

Author: frank-w

downloadfiles.py

@@ -33,7 +33,7 @@ def read_settings(infile):
             config[key]=value.replace("\n", "")
     return config
 
-config=None
+config={}
 conffile='sourcefiles_'+board+'.conf'
 if os.path.isfile(conffile):
     config=read_settings(conffile)
@@ -216,6 +216,8 @@ def getInitrdInfo():
 else: print(f"{board} not found in ubootfiles")
 
 newconfig={}
+newconfig["variant"]=config.get("variant","")
+
 if config and config.get("skipubootdownload"):
     newconfig["skipubootdownload"]=config.get("skipubootdownload")
     newconfig["imgfile"]=config.get("imgfile","")