Fix Meshnology W12 TX power

[oltaco]

This PR fixes reduced Tx power for Meshnology W12.

Default power is set to equivalent of roughly 22dbm, maximum power is set to the point where the FEM produces maximum output.

Measured using tinySA. Not ideal but good enough to see that Tx power is fully saturated when setting at 13dbm. Probably no benefit to setting it any higher.

Tx power setting	ProMicro HT-RA62 Measured	Meshnology W12 Measured
0	0.6	14.1
1	1.1	15.1
2	2.1	16.6
3	2.1	18.6
4	4.6	20.6
5	5.1	19.1
6	6.1	21.6
7	7.1	20.1
8	8.1	23.1
9	8.6	25.1
10	10.1	24.6
11	10.6	25.6
12	11.6	26.6
13	13.1	27.1
14	14.1	26.1
15	14.1	27.1
16	15.6	27.1
17	17.6	26.6
18	17.6	26.6
19	18.6	27.1
20	19.6	27.1
21	20.1	27.1
22	21.1	27.1