How can I safely charge a 12V deep cycle battery with a wind generator?
First of all you did not say how small is your battery.

Charging a Sealed Lead Acid to 14.0-14.8V is OK for cycle use - like charging it overnight, then disconnect the charger and slowly discharge through the day. If this setup is going to be permanently wired with the charger, a better option is to keep the voltage near the float levels - 13.2-13.8V.

Using a linear regulator is far from perfect. The main drawbacks are:


it will overheat at strong winds
you will loose valuable energy in heat dissipation, instead of storing it to the battery


I recommend you to find some CC/CV boost module (there are plenty ready assembled modules on the market for a couple of $)  whos output current can be limited to a value safe enough for the battery - like 0.1C or 0.2C max. C stands for battery capacity. (0.2C for 7Ah means 1.4A current.). Set the maximum output voltage to a value in between 13.2-13.8V or 14.0-14.8V depending on your battery specifications and usage mode.

Edit:
Some example of CC/CV boost module: