pySim-shell: Add 'decode_hex' command for transparent + linear EF

These commands can be used to decode a user-provided hex-string,
instead of decoding the data read from the file.  This is useful
for quickly manually decoding some values read from other locations,
such as e.g. copy+pasted from a eSIM profile in ASN.1 value notation.

Change-Id: I81f73bce2c26e3e5dfc7538d223bb2d2483c7fa0

docs/shell.rst

@@ -384,6 +384,13 @@ back to the record on the SIM card.
 This allows for easy interactive modification of records.
 
 
+decode_hex
+~~~~~~~~~~
+.. argparse::
+   :module: pySim.filesystem
+   :func: LinFixedEF.ShellCommands.dec_hex_parser
+
+
 
 Transparent EF commands
 -----------------------
@@ -460,6 +467,13 @@ to the SIM card.
 This allows for easy interactive modification of file contents.
 
 
+decode_hex
+~~~~~~~~~~
+.. argparse::
+   :module: pySim.filesystem
+   :func: TransparentEF.ShellCommands.dec_hex_parser
+
+
 
 BER-TLV EF commands
 -------------------