start/setup/update.sh: refuse to run on a Windows-hosted shell

A Windows user running the bash helper scripts (WSL, or Git Bash /
MSYS2 / MinGW / Cygwin) used to fail deep in the venv/PC-SC logic - under
WSL the Linux guest cannot reach the Windows PC/SC readers, and a
mingw/msys shell has the wrong (bin/) venv layout.  Each helper now
detects Windows (WSL via /proc/version, mingw/msys/cygwin via uname -s)
up front and exits 2 with a pointer at the matching .bat script.  Users
who deliberately want the WSL/Cygwin flow can run the underlying commands
directly, without the helpers.

Bumps VERSION to 3.40.4 and the SW cache to simple-v490.

pysim_simple_server/server.py

@@ -37,7 +37,7 @@ from osmocom.tlv import BER_TLV_IE
 from osmocom.utils import rpad
 
 
-VERSION = '3.40.3'
+VERSION = '3.40.4'
 
 MAX_ENVELOPE_SEGMENTS = 5  # max SMS segments for outgoing C-APDU in ENVELOPE