change python format for Bootrom (#442)

hw/ip/boot_rom/README.md

@@ -1,33 +1,5 @@
 ## boot_rom
 
-1. If you haven't done it yet, install [Conda](https://phoenixnap.com/kb/how-to-install-anaconda-ubuntu-18-04-or-20-04) as described in the link,
-and create the Conda enviroment with python 2.7:
-
-```bash
-conda update conda
-conda env create -f environment.yml
-```
-
-Activate the environment with
-
-```bash
-conda activate boot_rom
-```
-
-If you are already in the core-v-mini-mcu conda env, deactivate it first:
-
-```bash
-conda deactivate
-```
-
-2. Install the required Python tools:
-
-```
-pip install --user -r python-requirements.txt
-```
-
-3. Generate the boot_rom:
-
 If you modified the `boot_rom.S` file, generate it as:
 
 ```

hw/ip/boot_rom/gen_rom.py

@@ -89,9 +89,8 @@
 def read_bin():
 
     with open(filename + ".img", 'rb') as f:
-        rom = binascii.hexlify(f.read())
-        rom = map(''.join, zip(rom[::2], rom[1::2]))
-
+        rom = bytes.hex(f.read())
+        rom = list(map(''.join, zip(rom[::2], rom[1::2])))
 
     # align to 32 bit
     align = (int((len(rom) + 3) / 4 )) * 4;