[ESP32: SDMMCFS::begin hardcodes the usage of slot 1, only check if the pins match slot 1 pins.]

setPins() was testing pins D1, D2 and D3 all against D1 ... fine in 1 pin mode when all are -1 not so much if you're trying to get 4 pin mode working.
I now see this function doesn't really do anything on the ESP32...accept now correctly checks that you are trying to use the slot 1 pins.
Co-authored-by: NJan Procházka <90197375+P-R-O-C-H-Y@users.noreply.github.com>