multi trx lines

[gemu2015]

Description:

Related issue (if applicable): fixes #22034

multiple TRX line in SML header if line ends with comma
also adds special option to disable pull-up on RXD UART line

Checklist:

• The pull request is done against the latest development branch
• Only relevant files were touched
• Only one feature/fix was added per PR and the code change compiles without warnings
• The code change is tested and works with Tasmota core ESP8266 V.2.7.7
• The code change is tested and works with Tasmota core ESP32 V.3.0.4
• I accept the CLA.

NOTE: The code change must pass CI tests. Your PR cannot be merged unless tests pass