librem5: spl: bq25896: disable DPDM and ICO_EN
Enabling these causes USB errors on the host and device side. On the L5 we see
SDP: initialize... SDP: handle requests... Status: -108 Status: -108 Status: -108
And on the host side there are messages about failing to negotiate an address
Signed-off-by: Angus Ainslie angus@akkea.ca