store params in ~/.comma on PC (#2369)

common/params_pyx.pyx

@@ -7,7 +7,6 @@ from params_pxd cimport Params as c_Params
 import os
 import threading
 from common.basedir import BASEDIR
-os.environ['BASEDIR'] = BASEDIR
 
 cdef enum TxType:
   PERSISTENT = 1

selfdrive/common/params.cc

@@ -33,7 +33,7 @@ std::string getenv_default(const char* env_var, const char * suffix, const char*
 #if defined(QCOM) || defined(QCOM2)
 const std::string default_params_path = "/data/params";
 #else
-const std::string default_params_path = getenv_default("BASEDIR", "/persist/params", "/data/params");
+const std::string default_params_path = getenv_default("HOME", "/.comma/params", "/data/params");
 #endif
 
 #if defined(QCOM) || defined(QCOM2)