OOB read in Somfy io-homecontrol

[Mindavi]

Probably easy to fix, but I don't have time right now. Found using fuzzing.

Reproducer:

rtl_433 -y "5}fx6x50B005050050500505005050055x" -R189

Causes a segfault in somfy_iohc_decode, I think because the msg_len / data_length is not validated before using as an index.

[zuckschwerdt]

Thanks. Yes. Minimum msg length check is missing.