fix(el18): uart auto oversampling calculation #10625

Job	Run time
Run tests (x9dp2019)	2m 56s
Run tests (tx16s)	4m 54s
Run tests (nv14)	4m 45s
Run tests (el18)	5m 22s
Run tests (pl18)	5m 3s
Run tests (pl18ev)	4m 47s
Run tests (t12)	2m 43s
Run tests (t12max)	2m 35s
Run tests (t15)	4m 51s
Run tests (t16)	4m 48s
Run tests (t18)	5m 10s
Run tests (t8)	2m 32s
Run tests (tlite)	2m 32s
Run tests (t20)	2m 34s
Run tests (t14)	2m 50s
Run tests (t20v2)	2m 35s
Run tests (tx12)	2m 40s
Run tests (x10)	4m 51s
Run tests (x12s)	4m 51s
Run tests (x7)	2m 34s
Run tests (x9d)	2m 35s
Run tests (x9dp)	2m 30s
Run tests (x9e)	2m 33s
Run tests (x9lite)	2m 42s
Run tests (x9lites)	2m 45s
Run tests (xlite)	2m 34s
Run tests (xlites)	2m 31s
Run tests (mt12)	2m 38s
Run builds (nv14;el18)	4m 56s
Run builds (pl18;pl18ev)	4m 50s
Run builds (t12;t12max)	2m 23s
Run builds (t15;t16;t18)	6m 57s
Run builds (t8;zorro;pocket;mt12;commando8)	4m 21s
Run builds (tlite;tpro;tprov2;lr3pro)	3m 31s
Run builds (t20;t20v2;t14)	3m 4s
Run builds (tx12;tx12mk2;boxer)	2m 47s
Run builds (tx16s)	2m 49s
Run builds (f16)	2m 59s
Run builds (x10;x10express)	4m 49s
Run builds (x12s)	2m 50s
Run builds (x7;x7access)	2m 10s
Run builds (x9d;x9dp;x9dp2019)	2m 59s
Run builds (x9e;x9e-hall)	2m 9s
Run builds (x9lite;x9lites)	2m 5s
Run builds (xlite;xlites)	2m 11s
Run builds (mt12)	1m 33s
Package firmwares	3s
	2h 36m 7s

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