scripts: sercomm-pid.py: use uppercase hwid in pid

Sercomm uses uppercase for hexadecimal representation of the device
hardware IDs in factory image PID. This commit brings the sercomm-pid.py
script into compliance with the original Sercomm algorithm.

Example
-------
+--------+-------------+-----------+-------------+
| Device | PID (before | PID       | PID (after  |
| HWID   | the commit) | (Sercomm) | the commit) |
+--------+-------------+-----------+-------------+
| CPJ    | 43 50 4a    | 43 50 4A  | 43 50 4A    |
+--------+-------------+-----------+-------------+

Signed-off-by: Mikhail Zhilkin <csharper2005@gmail.com>

scripts/sercomm-pid.py

@@ -34,7 +34,7 @@ def get_pid(args):
 		enc = args.hw_version.rjust(8, '0').encode('ascii')
 		struct.pack_into('>8s', buf, 0x0, enc)
 
-		enc = binascii.hexlify(args.hw_id.encode())
+		enc = binascii.hexlify(args.hw_id.encode()).upper()
 		struct.pack_into('>6s', buf, 0x8, enc)
 
 	enc = args.sw_version.rjust(4, '0').encode('ascii')