ask for add ZXi ports

[LMN128]

Could you add access by ZXi ports too, please. Some SW use it. It comes better compatibility. Thanks a lot.
Info here: https://sinclair.wiki.zxnet.co.uk/wiki/ZXI_standard

tech spec:

ZX Spectrum SID on ZXi ports

h6C3B – select SID Control Register
h6D3B – read/write selected SID Control Register

Registers:
h00 to h1C - original SID registers

h1F - optional - select SID parameters
	bit 0 - SID type:  0-6581; 1-8580
	bit 1 - Frequency: 0-PAL;  1-NTSC (985248Hz for PAL C64, 1022730Hz for NTSC C64)
	bits 2-7 - always 0;
	note eLeMeNt ZX and MB03+ use FPGA implementation of SID that can switch type with related filters.
	
h20 - optional - select more SIDs (up to 256 SIDs) - useful for more than one SID
	       - in case of only one SID, is not needed to use it.