cc3200/tools: Fix exception raised on process failure.

subprocess.CalledProcessError() constructor arguments aren't documented,
but these are them.  Even if they change, it's an improvement over a
non-existent exception name!

Found by Ruff checking F821.
Signed-off-by: NAngus Gratton <angus@redyak.com.au>

ports/cc3200/tools/uniflash.py

@@ -41,7 +41,7 @@ def execute(command):
     if exitCode == 0:
         return cmd_log
     else:
-        raise ProcessException(command, exitCode, output)
+        raise subprocess.CalledProcessError(exitCode, command, output)
 
 
 def main():